heist vs hold to ransom

heist

verb
  • To steal, rob, or hold up (something). 

noun
  • A robbery or burglary, especially from an institution such as a bank or museum. 

  • A fiction genre in which a heist is central to the plot; a work in such a genre. 

hold to ransom

verb
  • To hold (someone) hostage until a ransom is paid. 

How often have the words heist and hold to ransom occurred in a corpus of books? (source: Google Ngram Viewer )