custodian vs washing-up liquid

custodian

noun
  • a janitor; a cleaner 

  • A person entrusted with the custody or care of something or someone; a caretaker or keeper. 

washing-up liquid

noun
  • A form of liquid soap used to wash dishes by hand. 

How often have the words custodian and washing-up liquid occurred in a corpus of books? (source: Google Ngram Viewer )