bleacher vs piazza

bleacher

noun
  • A stand of tiered planks used as seating for spectators, often outdoors. 

  • One who, or that which, bleaches. 

  • The tiered seating provided for the audience at a television filming. 

piazza

noun
  • A roofed gallery or arcade (for example around a public square or in front of a building). 

  • A public square, especially in Italian cities. 

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