A sand save is when you save par after going into a trap. Scrambling is when you miss the green in regulation (GIR) and still par.
For instance, on a par 3 where you miss the green and get up and down in 2 shots you "saved" your par. It usually involves only 1 putt so to increase your scrambling % you work on your short game-chips,pitches and flops.
The same applies to your sand trap play. Work on getting out closer to the pin for that makeable 1 putt. Flops and pitches work great from traps. GL