There was an interview where Thiago said he feels more Spanish than Brazilian. He's been playing for Spain since the u16 level and got capped for the senior NT in 2011, he ain't no Diego Costa. He's Spanish with a little Dinho in him.
Rafinha on the other hand is a good choice going forward for the Brazilian midfield. Industrial and hardworking, plus he's creative. I don't think he should've been called up as there were other more deserving players (Coutinho, Firmino) but he certainly would've been better than Bernard and could be a valuable member of that squad if he was in it.