A method can include receiving a search request from a user interface (UI), selecting one or more repositories in response to the search request, and displaying, on a display device, search results corresponding to the selected repositories. The selected repositories are a subset of a plurality of available repositories, as specified by an administrator. By selecting or de-selecting the available repositories, a user can define or refine a search of the available repositories. In various implementations, the method includes interface elements that assist a user in previewing revised search results based on revised selections of repositories, and/or selections of subcategories of information available in one or more of the repositories.