If no data is found via Recover from iTunes Backup File, following reasons may cause the data losing:
1. After the deletion, if the device has been synced with iTunes by connecting with your computer again, the backup file will be updated to erase the former data.
2. The lost data was never made backup with iTunes.
If you just deleted the data recently, please try Recover from iOS device.
If you have another iTunes backup files, please scan another iTunes Backup File for a try.