This actually worked on two of my systems when the results were not being shown.

Search and Indexing Troubleshooter

• Press Windows key + R

• Type in Control Panel and press Enter

• In the Control Panel search box type in Troubleshoot

• Then click Troubleshooting > View all

• Select Search and Indexing and click Next

• Let Troubleshooter run and fix all your search problems automatically

Note if you have not indexed your computer's search locations then index them. Also if run does not work then open cmd and run command control.exe to open Control Panel.

[Update 4/15/2022] - okay, so the *.jpg search on my 8TB folder was only showing ~14,000 results and now showing over 1.2 million results. that is good!! I did reset the Ownership and Permisson on my 8TB drive because it was messed up and Indexing and Search indicated a permissions issue might be at fault even after doing the troubleshooting index search wizards]

REF: https://superuser.com/questions/1534300/windows-explorer-file-search-always-returning-no-items-match-your-search