https://world.guns.ru/handguns/hg118-e.htm

If you're searching on Google, try various keywords such as blueprints, schematics, diagrams, and drawings, along with the gun type (rifle, pisto, machine gun, etc.). there are a ton of images out there.

You might also look are any of the numerous gun afficionado magazines. They are full of photos and often include drawings. Good luck.