Searching options inside platform/projects

It would be amazing to see a tool that allows some internal searching to put some content and let you know which project/chapter/section is related to. Sometimes users have a lot of files and internal projects and they might not remind which one was the text they were working with, but they remember some passage for that file and a searching tool would be doing wonders to find those projects easily.

An star system for documents can also be beneficial, so the users can search for the started documents.