[@rezay] ah i got it.
They use animals they find dead for their hides. Primarily for yurtas.

As for some plant fibers, sure flax is kinda advanced, but making something a bit more fabric-like than the raincoat example should be possible.
I mean, there's plants you just open up, drag out the strings inside and dry them. Makes rudimentary strings one can weave into things. Not full on dense fabric but certainly good for some clothes.

But yeah, either they go naked or hides otherwise. And hunting for hides doesn't make massive sense.