To search for tags or pornstars. Add tags|pornstars in front of your search. For example pornstars:karma rx. You may also use quotes to make it strict. For example: tags:brazzers.
To search only from posts use posts:s in front of your query. Quotes around your query make the search strict. For example posts:"staff thread". To search specific content type in posts use type:video|image|gif. For site specific searches use the site:example.com attribute. And last but not least, if you want to search by status then status:solved|unsolved|featured|thread|deleted. For image reverse search, go here.