Not found the game

You can't, they were free.
https://www.steamgifts.com/discussion/pJRbR/can-we-have-a-list-of-games-that-cannot-be-created-as-giveaway-unofficial-list-inside

That is why you find the game first in the search bar then make a giveaway.

i only find one thread https://www.steamgifts.com/discussion/4rlVq/three-free-games-on-splitplay-the-box-goldak-and-face-it-drm-free
But that was drm-free version, not for steam :О