Enchantment in 17w06a seems broken

Okay, so I started a new world in Survival Mode in the 1.12 Snapshot about 5 days ago. On the second day in the world (second real life day playing the world) I set up an enchantment spot and began enchanting. I got Eff3 and Unbr2 on my pick really fast, and got sharo3 pretty fast as well.

That's all the enchantments I can get.

The ONLY enchantments I've gotten are Efficiency, Protection, Feather Falling, Aqua Affinity, Unbreaking, and Sharpness. That's it. Today I finally got something with Sweeping Edge, but this is the first time in 4 days of grinding that I have gotten it.

I've used 2 and a half stacks of diamonds on armour and items and that's it. I think it could be luck, but considering how many freaking tries i've done on a Pick and gotten ONLY Eff and Unbr, I'm sure it's a Snapshot bug. If it is, is there a way to fix it in the client, or is it a system bug that needs a game update?