go away vs rack off

go away

verb
  • To vanish or disappear. 

  • To depart or leave a place. 

  • To travel somewhere, especially on holiday or vacation. 

intj
  • A command encouraging someone to leave. 

rack off

verb
  • To go away; to sod off. 

  • Used other than figuratively or idiomatically: see rack, off. 

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