This interface is designed to allow you to filter a list of talks by organisation, event or speaker. So if, for example, you wanted to see a list of talks by Satish Kumar for Resurgence at any event you could achive this by selecting resurgence as the organisation, none as the event and Satish Kumar as the speaker then click 'show me some talks'. To find any talks by Satish Kumar for any organisation you could do the same but with organisations box set to none. You can also make multiple selections in each box , this would allow you to add talks by Vandana Shiva to the previous list by pressing Ctrl and clicking 'Vandana Shiva' in the speakers box. Don't worry you cant break anything :)