Using Get-PWDocumentsBySearch to locate files by Property values

I am trying to find a way to locate all the files in my datasource that are associated with a defunct application and associate them with a "new" application. I have not been able to find a way to search on files based on their property values  - such as "Application", "Status", "Workflow" etc. Has anyone done this a bunch and can point me in the right direction?  Thank You!