They look like screws used for furniture or for some type of composite “wood.” That’s based upon what I can see of the remaining threads. The bigger issue is that those heads are broken off, so the remaining screw threads are still in place; once found, they will either have to be drilled out to use the same location, or new screws put in adjacent to where the broken ones were. Good luck on finding and fixing, and let us know when you find where they came from, so we’ll know what to keep an eye out for.