Dry humor — of the kind that doesn’t really try to make you laugh, and succeeds — gets a workout in writer-director Andrew Bujalski’s thin rom-com “Results.”

Cobie Smulders plays a brittle personal trainer whose new client (Kevin Corrigan) is a rumpled tech zillionaire rattling around a house the size of an art museum. Meanwhile, at work, she’s having an on-again off-again fling with her boss (Guy Pearce), an irony-challenged self-help proselytizer.

As the characters engage in aggressively eccentric behavior (jogging with a large cat; blurting out, “Do you want to make out?” in the middle of an unrelated conversation), the movie can be mildly amusing. But I couldn’t figure out which of the three principals I least wanted to know; moreover, though they hop into bed, none of them seems especially attached to their love interest. If they don’t really care, why should we?