This article describes how to find and relocate orphaned files in Google Drive.
Orphaned files are files that belong to you, but don't show up in your directory structure. Therefore, you can't find it by browsing your folders. This occurs when someone deletes a folder where a file you own resides.
There are two different ways to recover orphaned files.
Either way you use, once you have found the file, you can move it to a location of your choosing.