brush off vs laugh away

brush off

verb
  • To disregard (something), to dismiss or ignore (someone), as unimportant. 

  • Used other than figuratively or idiomatically: see brush, off. To remove something with a brush. 

laugh away

verb
  • To dismiss something as unimportant. 

  • To pass the time with frivolous and amusing conversation. 

How often have the words brush off and laugh away occurred in a corpus of books? (source: Google Ngram Viewer )