nonplus vs snarl up

nonplus

verb
  • To bewilder or perplex (someone); to confound, to flummox. 

noun
  • A state of bewilderment or perplexity. 

snarl up

verb
  • To put into disarray; contort; confuse; muddle up 

  • to become congested. 

  • To become tangled; to become entangled 

  • to entangle 

  • To block (traffic); to cause (traffic) to be congested. 

How often have the words nonplus and snarl up occurred in a corpus of books? (source: Google Ngram Viewer )