陈谷子烂芝麻

Explanation: Metaphor does not matter if old or something. 　　Source: Lao She, "Four Generations" two need a old friend, good to have a place to play his Chen Guzi bad sesame. " 　　Examples: Need a old friend, good to have a place to play his Chen Guzi bad sesame. (Lao She, "Four Generations" b)