dragnet vs fish for

dragnet

noun
  • Heightened efforts by law-enforcement personnel to capture suspects. 

  • A net dragged across the bottom of a body of water. 

verb
  • To make heightened efforts to catch a suspect. 

  • To drag a net across the bottom of a body of water. 

fish for

How often have the words dragnet and fish for occurred in a corpus of books? (source: Google Ngram Viewer )