Specify criteria to search exchange 2010 backup

I am attempting to search my Exchange backups for email messages from a specific domain. When I try to enter data in the Content: field in the search wizard, the search doesn't use it as a filter. If I Copy Criteria To Clipboard and past the criteria into Notepad, all that shows is that the Search is looking for Mail Messages, not including the string in Content as part of the search.

 

Anyone have any ideas how I can search the whole database for a specific from domain?