The text box is available only if the Selected diagrams option button is selected.
In the Select diagrams box, type the name of the diagram you want to find. Search results are displayed as a model tree or a plain list right under the text box. Click the Tree or List tab in the search result area to switch to the desired view, and select the diagram(s) you want to save as image(s).
To optimize your search, use search modes and scope filters. The Apply Filter check box and the filter options button are located below the search result area.