Since 1.14 player can enchant his armor by "protection" AND "projectile protection" AND "blast protecion" AND "fire resist" on one item together.

And player can find armor in dangeons with that enchants together on one item (chest, legs...). 

In 1.13.2 it was impossiable. Player must choose single enchant: "protecton" OR "projectile protection" OR "blast protecion" OR "fire resist".