draw back vs regrade

draw back

verb
  • to move backwards 

  • to pull something back or apart 

  • to withdraw from an undertaking 

  • to retreat from a position 

regrade

verb
  • To regroup or reassign. 

  • To change the classification of (potentially secret documentation). 

  • To grade again, give a new grade or grading to. 

noun
  • The act or process of grading again. 

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