entresol vs flooring

entresol

noun
  • A mezzanine; an intermediate floor in a building, typically resembling a balcony; most often, the floor immediately above the ground floor and below a higher floor. 

flooring

noun
  • A floor. 

  • The act of putting one's opponent on the floor; a knockdown. 

  • A material used to make floors. 

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