move ahead vs move on

move ahead

verb
  • to proceed; to make or signify progress 

  • to continue without being distracted; to keep going 

  • to go on to something else 

move on

verb
  • To continue, to proceed, to go on 

  • To start dealing with something else. 

How often have the words move ahead and move on occurred in a corpus of books? (source: Google Ngram Viewer )