Hi, I have found testdisk to be very useful.
If you have it installed you may find the installed docs here...
But I think both testdisk and photorec are for recovery of files from a whole partition.
It may be useful if you know the file types you want to recover, and a spare partition of the same size or larger.
Both dd-rescue with dd_rhelp, and ddrescue are for whole partitions too.
Sorry I can't point you in the right direction, maybe you could brows for it here..