My 2 cents , If you are woman and u are single , You need to seem more approachable and pay attention to the dude who is checkin you out , Usually the problem you state occurs to men mostly since they have some issues , otherwise women get approached all the time , So therefore just be more open , if a guy comes to you and asks something silly know that he is flirting with you and engage him in some conversation.

If you are a guy , then I suggest you either read posts from this website http://www.sosuave.net/ a website dedicated to guyz who cant get women , Personally read the "The Book of Pook" , and dont be discouraged if your friends laugh at you beacuse you are reading a book that tells u how to get girls , pretty soon you will have the hot gals chasing you and your friends will then only stare at you in wonder and awe !