To open a questionnaire in AskiaVista:
At the top of the screen, click Open. The Open questionnaire modal window appears:

If you have a large number of surveys, you may find it easier to search for your questionnaire by name, rather than scroll through the list. To search, simply type the survey name, or part of the survey name, in the search box at the top of the window:

Click the questionnaire you want to open, then click Open. Alternatively, you can double-click a questionnaire to open it.
To close the window without opening a questionnaire, simply click Close.