split off vs walk away

split off

verb
  • To break away from a group or mass. 

walk away

verb
  • To withdraw from a problematic situation. 

  • To free oneself from a debt such as a mortgage by abandoning the collateral to the lender. To make a strategic default. 

  • Used other than figuratively or idiomatically: see walk, away. 

  • To survive a challenging or dangerous situation without harm. 

How often have the words split off and walk away occurred in a corpus of books? (source: Google Ngram Viewer )