To obtain this achievement you need to dig up 10 items, anywhere in the game. The desert does have 10 items itself. Having the pet Fazzo does help because he/she shows you where treasure is located.
Video was done by AchievmentBasher
How to acquire your save from the 360 (and unlocking the desert without having to fight every enemy getting there):
You can load your characters from the 360 version by loading the game up on your 360, click player statistics on the main menu and hit RT this will que them on the One.
Once you have done the first step load the game up on the XBOX One and go to the 3rd button in the bottom right corner of your button selection on the menu, hit A, then X to download all your 360 save data.