You can use collections in the content browser to select/tag commonly used assets. An asset can be in multiple collections at once, so e.g., you could place Rock01 in Rocks, Biome_Hardscrable, and LocalFavorites collections. Collections also work for search/filtering as well, so if you had a mesh called Boulder in a collection named Rocks, typing Rock B in the Ctrl+P menu will find it.
Cheers,
Michael Noland