If lost files were on deleted or damaged partition, then procedure of file recovery is slightly different then Recover files and folders from existing volume.
Apply scan directly on physical drive (disk), ignoring its logical structure in order to detect deleted (damaged) partition. For exact scan procedure read: Scan for deleted partitions and files by their signatures on page 18 article.
A disk scan result appears in the Work with device scan results on page 19 view where results can be reviewed and files selected for recovery.
Detected partition can must be scanned in a same manner as existing volumes. Follow recommendations in Recover files and folders from existing volume to continue.
If files was detected already by their signatures no further steps are necessary — use Recover detected files procedure to recover detected files to the safe location.
Review in scan results group of files detected by their signatures or detected partition scan results. Repeat steps 1-3 using different scan attributes for better results if necessary.