uphold vs walk back

uphold

verb
  • To support by approval or encouragement, to confirm (something which has been questioned) 

  • To keep erect; to support; to sustain; to keep from falling 

  • To hold up; to lift on high; to elevate. 

walk back

verb
  • To withdraw or backpedal on a statement or promise. 

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

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