Since a majority of Android phones do not have a recycle bin, you cannot retrieve your data back through it. When that space is occupied by original files, you can say your file is lost. Hence, you cannot see the file, and that space can be overwritten by new files. Android marks that space as empty and treats the file as missing. The catch here is that on deleting a file, its data is not washed away entirely.
How does Android Data Recovery Software work?
