If you lost data from your android phone,
the first thing, check out the backup, whether you have synced the data to Gmail account, or saved on your pc.
Then, you should never add more data to your phone after data loss, cuz they can take up more space, the lost data will be overwritten.
Last thing, you can try android recovery methods, Recuva, you can also try professional data recovery programs.
How to recover deleted photos.