blow hot and cold vs think twice

blow hot and cold

verb
  • To behave inconsistently; to vacillate or to waver, as between extremes of opinion or emotion. 

think twice

verb
  • To reconsider, use judgement; to proceed with caution or thought. 

How often have the words blow hot and cold and think twice occurred in a corpus of books? (source: Google Ngram Viewer )