CRM 4.0 Get the FetchXML queries in Advanced Find

You can just open the Advanced find page and build the query as you like. Then run the query to see if it returns the data as you wish it should. Press F11 to get the address bar and enter this script and press enter.

javascript:alert(resultRender.FetchXml.value);

or

javascript:prompt("my query:", resultRender.FetchXml.value);