Test Set/Test Plan search option "+" under Test Repository, should be labeled

While adding Tests to the Test Set or the Test plan, a search window opens. The + sign should be labeled for the usage as it opens up all the issue types and not any specific ones like Test Set or Test Plan

Also, after clicking on + sign, the window should show either the specific issue types (Test Set/Test Plan) or the issue type column should present over there to identify.