Re: Sims 4 Gallery - Limited Results

On the options menu (game options) uncheck the "hide reported content" button

This should bring up much more in the gallery.

Also, in the gallery itself, there is a show creations that use cc button, you can click that as well if you don't mind downloading stuff that may or may not have changes when you download it.

Try clearing your cache and reloading the game (Crinrict has a great guide here): https://sims4.crinrict.com/eng/2014/09/delete-cache-files/

You can also try repairing the game through Origin.