1. User fills in the search box in the navbar or search results page and submits the query.
2. System validates and runs the query.
3. User is redirected to the results page.
4. User can change the displayed results to show only models, groups or users.

2.
    a. The query is empty or contains an error
        1. User is notified of the error and no results are displayed; Use case continues at step 1.