What does 'have a false bone in his body' mean?

"He doesn't have a ____ bone in his body" is a way to state something about another person with strong emphasis. For example: "He doesn't have a mean bone in his body" would obviously mean that not only is this person not mean, but he is never ever mean, even to the slightest extent. "He doesn't have a deceitful bone in his body"... you get the idea. You would use this kind of construction in casual speech, and you may encounter it in writing, but it would generally be considered trite rather than creative.