Problem With final Clean UnWrap (Bake Texture and normal)

Greetings everyone,
i am new in blender, i have problem with bake uv mapping, i was create multiple material and then i want to merge all material into one image by using bake texture,
i follow tutorial from youtube start from minutes 36:50,
the video tell me to make new uv maps and then unwrap all the obejct in the new image, then adjust the uv mapping of all object…

the problem is, When I bake textures onto model , regardless how big the uv islands are, the textures appear to be low quality , and the normal maps don’t give detail after baking,but in the video, the textures look crisp after baking,how? I use 2K and sometimes 4K textures aswell,and bake in blender render .
here is bake in video :

here is bake in my pc :

if anyone actually know my problem, please tell me, i have been stuck in 2 days :spin:
sorry for my english,
Thanks…Store building_backup.blend (1.28 MB)

here is my assets file : assets

You have failed to supply a demo blend file and all relevant textures (something you MUST do for ALL support questions) so we do not know how you have set up your materials !!

That’s my fault sir. I’ve edited my post.