recover files that emptied in the trash

Check iCloud and See if these Items are in there.

Rather than purchase an App, You might want to go here:

Add your Desktop and Documents files to iCloud Drive - Apple Support

Scroll down to: Turn on Desktop and Documents.

Having already enabling this, and upgraded, iCloud would have already stored certain items in there. This is a method of saving space on your Mac.

Having upgraded iCloud, you would have increased the quantity of items stored, and that means there may be better possibility of them being retrievable. In particular, this would be the case is minimum system requirements are met to do so.

EaseUs is a good one. You can use the free version that's limited to up to 2gb worth of file recovery.

https://www.easeus.com/mac-data-recovery-software/drw-mac-free.htm

It will show you everything it can recover though so if you have more than 2gb of data to restore you'll just need to consider buying the full version of the program.

You can't recover files deleted from the trash other than by getting them from your backup.

The absolute best is to restore them from a backup.