doss down vs zizz

doss down

verb

  • To sleep on someone's sofa or floor because there is no bed spare. 

zizz

verb

  • To take a nap. 

noun

  • A buzzing or whizzing sound. 

  • A nap or sleep. 

How often have the words doss down and zizz occurred in a corpus of books? (source: Google Ngram Viewer )