"Fall on deaf ears."

I know of only one person in my time who really didn't say much but did so well to get their point across. They'd actually sit and listen to every word I'd say... make like they were absorbing all my efforts to communicate with them... nod their head as if to encourage me to continue and when I was done they'd shake their head and walk away like I hadn't said a word. It's amazing what one person can teach you in so few words.