Abstract: A criteria search performed by a search engine comprises associating each of a plurality of users with at least one knowledge domain, associating a user's query to at least one subject area in the at least one knowledge domain, and generating search results based on the user's query and the at least one subject area. A search engine comprises a plurality of search repositories configured to perform different types of searches and a search component. The search component receives a search query from a user, modifies the query based on one or more knowledge domains that the user is associated with, submits the modified search query to the plurality of search repositories, and receives search results from the plurality of search repositories.