duke it out vs get to grips with

duke it out

verb
  • To fight, especially with the fists. 

  • To argue heavily or at length. 

get to grips with

verb
  • To battle (with something). 

  • To deal (with something) decisively, or to confront (it) head on. 

  • To gain an understanding (of something). 

How often have the words duke it out and get to grips with occurred in a corpus of books? (source: Google Ngram Viewer )