prefer vs strike gold

prefer

verb
  • To be in the habit of choosing something rather than something else; to favor; to like better. 

  • To present or submit (something) to an authority (now usually in "to prefer charges"). 

strike gold

verb
  • To be lucky, to win or be successful. 

  • To find gold 

How often have the words prefer and strike gold occurred in a corpus of books? (source: Google Ngram Viewer )