pipework vs vas

pipework

noun
  • The pipes and stops of an organ 

  • Any system of pipes or tubes; piping 

vas

noun
  • A vessel or duct transporting any bodily fluid, such as blood, lymph, chyle, or semen. 

  • The vas deferens. 

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