run away vs take on

run away

verb
  • To leave home, or other place of residence, usually unannounced, or to make good on a threat, with such action usually performed by a child or juvenile. 

  • To become a runaway. 

  • To flee by running. 

take on

verb
  • To assume or take responsibility for. 

  • To (attempt to) dribble round (an opposition player). 

  • To catch on, do well; to become popular. 

  • To obtain the services of (a person) in exchange for remuneration; to give someone a job. 

  • To begin to have or exhibit. 

  • To attempt to fight, compete with, or engage with. 

  • To acquire, bring in, or introduce. 

  • To grieve or be concerned (about something or someone). 

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