double-talk vs hem and haw

double-talk

hem and haw

verb
  • To mumble and procrastinate in one's speech, especially with a reply to a hard question or with voicing a decision on a topical matter; to evade a question, giving vague answers; to equivocate or temporize. 

  • To discuss, deliberate, or contemplate rather than taking action or making up one's mind. 

How often have the words double-talk and hem and haw occurred in a corpus of books? (source: Google Ngram Viewer )