A family of Microsoft word processing software products for creating web, email, and print documents.
My search is for a keyword in the document content.
I have since established that the initial search yields a list of files (if any) where the keyword is in the file name only.
Then, at the bottom of this list, additional options are given (which I missed on previous occasions):
When I select 'File Contents' here, it does actually search the contents of the filie.
Thanks to everyone for your input.