move ahead vs persevere

move ahead

verb
  • to continue without being distracted; to keep going 

  • to proceed; to make or signify progress 

  • to go on to something else 

persevere

verb
  • To persist steadfastly in pursuit of an undertaking, task, journey, or goal, even if hindered by distraction, difficulty, obstacles, or discouragement. 

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