抠心挖肚
      Explanation: Dug out the heart of the belly. Describe bother thinking.
      Usage: Joint type; as predicate; that rack their brains
      Source: Qing Zhang Chunfan "officialdom" 11 back: "We heard the small end of the Retroflex Suffixation wood, one by one to pull the belly of the heart to dig a lot of law to children."
      Examples: Eaten dinner that day, leaned Yanta, and ~ the full article to be a night of Chen manuscript, not yet drawn. (Qing Li Baojia "Bureaucrats," the second time)