If you have many agents and you want to provide search ability for your agents you can use "WPL Search Widget" for users. Navigate to Appearance->Widgets and place WPL Search Widget into "Profile Listing Top" position (or any position that you like).

Note: For this you should have WPL Membership addon.

After placing the widget, set the kind to "User" and select your agents page as target page. Please check following figures:

Also, you may learn more about the WPL Search Widget here.