I have tens of thousands of files in a corrupted usb drive,
I use Recuva to recover them and they are all saved on my HDD in a Backup directory.
The recuva recovered them and preserved their file type, but not file names.

This is my situation.

IF I am thinking of my CV, inside has my address, let's say "10, George Road",
how to search among those WORD files containing "10, George Road" ?

Why not test the Konqueror search?

Start if off, go make dinner, then come back and see whether it worked.

When I did my test, I searched for files with my name in them and Konqueror found scads of them in multiple formats. (I don't use Dolphin simply because I really like Konqueror, but I suspect it has the same capability.)

yes, it works,
but only libreoffice files can be searched, not Ms Office.
I had tested it,
the same file saved in both xls and ods formats,
only the ods file is displayed to contain the contents I keyed in.

If I click the option "binary", it takes longer time and many files are displayed.