踏破铁鞋无觅处，得来全不费工夫

Explanation: Metaphor needed something with a great deal of effort to find, but inadvertently obtained. 　　Source: Ming Feng Meng, "Jingshitongyan Show gold Lingshi Meibi pay child": "with gold and closed the door, and two Cuxi go into the details. Is: wear out iron shoes in hunting, must come to not a waste of effort!" 　　Examples: Hate the small non-gentleman, non-toxic does not her husband. It is: ~. (Ming Feng Meng "Jingshitongyan" Volume VIII)