how to recover deleted files from trash. My device is a MacBook Pro running OS X 10.11
The deleted trash should be moved to the Trash can on the far right side of the Dock. Just right-click and choose Put Back.
I have already performed some tasks on Mac and can not undo the deletion, when I check the deleted files in Trash, there are not there! I guess I have permanently deleted them from my Mac using keyboard shortcuts, and they disappeared bypass the Mac Trash.
If you can’t find the deleted files in Mac Trash, have you backed up those files before the deletion such as Time Machine, iCloud, etc.? Having such a backup to restore the deleted files could be good news. Otherwise, you can try third-party data recovery software such as Free Download iBoysoft Data Recovery for Mac to recover the deleted data as long as they are not overwritten.