retain vs run with

retain

verb
  • To hold back (a pupil) instead of allowing them to advance to the next class or year. 

  • To employ by paying a retainer. 

  • To keep in one's pay or service. 

  • To keep in possession or use. 

  • To hold secure. 

run with

verb
  • To take an incomplete or inadequate (plan, text, etc.) and develop it further, often with the implication of carelessness. 

  • Used other than figuratively or idiomatically: see run, with. 

  • To be a member of (a gang, hooligan firm, etc.); to associate with a, typically disreputable, individual or group. 

  • To follow something through to completion or realization. 

  • To be streaming with a fluid. 

How often have the words retain and run with occurred in a corpus of books? (source: Google Ngram Viewer )