Are yo saying that your past purchases are not listed here?
Downloading past purchases from the App Store, iBookstore, and iTunes Store
Is the device signed into the account that pourchased them?
If you log into your account in iTunes>Store>View Account and go to Puchase history are they listed?
Does your country allow redownloading, not all do?
iTunes in the Cloud and iTunes Match Availability
Does the music play i iTunes?
You can try:
- Restore from backup. See:
iOS: How to back up
- Restore to factory settings/new iOS device.