What does it mean if someone says that you have a Mona Lisa Smile?

Mona Lisa is a renaissance painting often described as the lady with a mysterious smile. It kinda mean that her smile looks like she knows something that others don't. Makes one look or try to observe the painting more to understand what it was. But it remains a mystery to most except for the artist. The person who told you that must mean that you are a very interesting person and would like to get to know you more.