I was wondering if there is anything that can be done to snow quartz to make it not break so easily?
There is nothing you can add to the surface of the stone, but you can create the jewelry in a way that will help protect the stone from damage when worn.
Gemstones can be mounted in metal settings which help protect them from breakage. Premade bezels are designed for stones cut to a calibrated size so they can be paired together well. Instructions for setting stones in bezels can be found in the resource section below.
If your stone is more of a freeform shape or doesn't match a calibrated setting, you can create your own setting using bezel wire and a few metalsmithing tools. Instructions for creating your own setting can also be found in the resource section below.