firewood vs woods

firewood

noun
  • Wood intended to be burned, typically for heat. 

woods

noun
  • A dense collection of trees, usually one covering a relatively small area; usually smaller than a forest. 

  • For chemical behavior purposes, trees in full leaf (coniferous or medium-dense deciduous forests). 

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