look back vs reminisce

look back

verb
  • To think of (past events) in retrospect. 

  • Used other than figuratively or idiomatically: see look, back. 

  • To reconsider or regret. 

reminisce

verb
  • To recall the past in a private moment, often fondly or nostalgically. 

  • To talk or write about memories of the past, especially pleasant memories. 

  • To remember fondly; to reminisce about. 

noun
  • An act of reminiscence. 

How often have the words look back and reminisce occurred in a corpus of books? (source: Google Ngram Viewer )