make nice vs soften

make nice

verb
  • To be friendly or conciliatory towards another, often in the context of maintaining good relations or resolving a conflict with the other person. 

soften

verb
  • To undermine the morale of someone (often soften up). 

  • To make something soft or softer. 

  • To palatalize. 

  • To become or make (a consonant) more lenis, to lenite. 

  • To make less harsh 

  • To become soft or softer 

How often have the words make nice and soften occurred in a corpus of books? (source: Google Ngram Viewer )