come back vs start over

come back

verb
  • To return to a place. 

  • To return to one's possession, especially of memories. 

  • To retort. 

  • To return to a former state, usually a desirable one; to become fashionable once more. 

start over

verb
  • to begin again; to return to the beginning 

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