Its something that bugs me but, with some research and help from a friendly bowguy (He finds Bowyer sounds too fancy and 13th century) I got an answer that I am happy to discuss on to drek bows so I am gonna talk about it

So why take a bow?

Hunting weapons are pretty important to drekir, they're mesocarnivores and hunting, fishing, and foraging meat sources is necessary for them to live which tends to mean that they engage in a variety of hunting tactics with a variety of things. Everything from trapping and snares to hunting with atlatls and fishing with nets. Different cultures might come up with different tools for different jobs and situations Most of the ranged weapons are not necessarily substitutes for others. A crossbow has different pros and cons than an atlatl for example and bows are no different though, granted.

Bows are possibly one of the most widely adopted preindustrial weapons of humanity throughout all of written history and a sizeable chunk of prehistory in every place in the world except Australia.

While bows are versatile, drekir bows would be less varied than the wide breath of bows we have
Drek bows are more specific due to the narrow size and power range that they can exist in. Cramped environments, regions that are lacking in large amounts of wood , needs to be constantly on the move chasing and shooting at prey, or possibly different preferences.

So the "Drek Bow"

Drek bows, by necessity are going to be very specific in their structure, size, power, draw length etc. as they are pushing up against a lot of the limitations of the drekir in a lot of ways. The bow staves length (length of the bow when unstrung) tends to be somewhere between 36-43 inches or so, maybe 45 inches tops (about 90-115cm) or so. Moreover, their intended draw lengths are also short, with the ideal draw being between 18-24 inches tops (45-60cms or so)
and the poundage of these bows being light, ranging between 30-40lbs for more serious bows and, with some serious training, a drek might build up the epic strength to pull bows that are between 40-45lbs.
And there would likely be even lighter bows that rely on specializing in small animals or using poison as a hunting tactic that might be more around 20-25lbs
Of course 30-40lbs tends to be a solid hunting bow for small and mediumish folks, and can take down larger animals with good shot placement (or a lot of arrows if a humane death isn't in order). The problem is that the arrow will lose its power very quickly, so this limitation would put a dreks bows effective range within the range of a lot of their other hunting weapons that one could make, under 30 meters or so (about 33 yards). Anything further is just going to lose too much power to actually be deadly (but probably painful)

As for materials
There are a variety of woods of course, Osage, Willow, Ash, Elm, etc. Wood being the tried and true method. Drekir bows would probably mostly be flatbows as they are easy to make, less prone to breaking, and are less picky in types of wood. But its not the only material.

Bone and Horns have been used to make bows. There are shortbows that are just made of two ground and shaped horns that tend to fit in this size range (by necesity, horns tend to be limited in size) And bone bows do exist but... are rare. Maybe less rare amongst the drekir but still probably not common as they are difficult to make

Scavenged materials may not be favorable. If it can be found as a rare and lucky find, fiberglass of course makes a great material for bows.
PVC, while everyone would say make it into a bow would not work particularly in the dragonscape. Though its great for bows if made properly, the PVC of the dragonscape has been sitting in the sun for well over a century which would likely make that PVC highly brittle, assuming it hasn't shattered already
so the PVC of the DragonScape is not nearly as useful as what you might find at the hardware store. If anything I would more likely see drekir using it to make arrowhead/projectile points rather than a bow.

And lastly antler, kinda the same as bone but far rarer as antlers only really appear in the far northern arctic regions of North America, but there? probably
So generally speaking, Wood, Horn, Fiberglass, Bone and Antler are all good materials.

and as for shooting styles

Of course drekir might invent multiple shooting styles but so far I only got one on the mind so if you guys got thoughts on other neat ways of shooting mini knives at things let me know. But the general style involves aiming the bow in an arc in front of you, at least on your shooting hands flank and in the front. The bow is held horizontally and the arrow is knocked on the topside of the bow. The draw is towards the crook of the neck, basically the base of the neck where the neck and collar transition to the sternum and ribs as it's kinda an easy gap to pull the arrow towards.
With the arm straight, depending on the length of the dreks arm and draw, will be close to 19 inches and the draw is not held. Rather the drek is going to ideally be releasing the arrow as soon as the arrow hits the end of the draw. So its not a "draw, aim, and release" but rather it's an instinctively aimed push/pull and release as quickly as possible
This style also does not interfere with the legs allowing a drek to move while slinging arrows which is a big advantage of the bow

And as some other thoughts

The first probably being an explanation why I keep trying to get bows to work. It's mostly that bows are one of the most famous weapons across the world and most countries have some knowhow of bows if not a lot of experience. Across the Americas Bows are used in modern bowhunting, traditional bowhunting and is used today across all of the americas and. Even if you're not a guy who knows their way around a bow, you have probably seen a lot of them
This sort of general understanding of a bow is probably going to bias a lot of 1st gen drekir in the early years to make one as its probably the first thing that will come to mind on average

a sort of "Man sprinting at things with a sharp stick with my friends kinda works... but I bet I could try and make a bow to make this easier" Even if things like atlatls, slings, etc. can get more power

which may result in some drekir groups trying to make bows, not hitting the right recipe and/or giving up for things like atlatls or throwing sticks, while other groups of drekir get a good bow figured out at some point (doesn't have to even happen just in the 1st generation). Then that info gets passed down from the adult to the annoying little mongrel who keeps asking them what they're doing with the piece of wood
so yeah. Arrows are gonna be more straightforward so ill get back to that later but yeah bows
I think this is a pretty good overall explanation. It may not be the most dominant weapon of the dragonscape for hunting and fishing (as it would be used for both depending on the culture) but I think I am confident that it would exist and it would probably exist in the above way