In my installation of FileLocator Lite (Build 825 on a Windows 7 system) I found that .odt files were no longer found by supplying a (matching) filename prefix and a (matching) content search term when "Office/PDF documents" is checked under "Enhanced Document Searching" in "Options".
The only recent change to the system, apart from regular Windows updates, was a recent update to LibreOffice. Could that indeed cause problems, and how can I solve them?