I think it's just more that they are very good at hiding their true thoughts. The only reason it's so obvious for us is that we can see their inner thoughts and feelings.
Okay, I thought there was some supernatural explanation for why they don't notice him. No, she's definitely doing it on purpose for some reason. She probably doesn't like him, considering that it isn't tagged as a romance.
I mean, I HAVE stopped reading. A while ago, in fact. If you idiots would stop whining about me writing my opinions, you wouldn't have to read My comments at all.