ang tagal na nun boss. baka na wipe na yun and totally unrecoverable..
kasi, the way data recovery works is that it will search the storage on the original directory that the files are saved. when you erase a file, it only erased the index that point to where the file is but not file itself, at least for now.. over time, if you save other files it will overlap on the previous saved files (which are supposed to be erased for quite some time), and in turn overwrite data stored.. It will render the first file to be unrecoverable (or sometimes partly corrupted)...
another reason that files may not be salvaged is if you thoroughly shred your storage using data shredder softwares.