reconsider vs sing a different tune

reconsider

verb
  • To change one's mind, with or without actually considering the matter again 

  • To consider a matter again. 

sing a different tune

verb
  • To hold to a different opinion or appreciation (about something); to possess a new, changed, or regenerated mindset, usually for the better. 

How often have the words reconsider and sing a different tune occurred in a corpus of books? (source: Google Ngram Viewer )