I was trying to enchant diamond boots with protection 4 and feather falling 4, and I did the command brackets correctly. Instead of Protection 4 and Feather Falling 4, instead I get Prot 4 and Prot 4.
To reproduce:
1. Get a command block
2. Type in this command:

/give @p diamond_boots 1 0 {Unbreakable:1,ench:[{id:protection,lvl:4},{id:feather_falling,lvl:4}]}

3. Give it a whirl and check the boots.