puff pastry vs strudel

puff pastry

noun
  • A light, flaky pastry that is made of alternating buttery and floury dough layers by repeatedly folding the rolled pastry into many layers. 

strudel

noun
  • A pastry made from multiple thin layers of dough rolled up and filled with fruit, etc. 

  • Synonym of at sign (@) 

  • A vertical hole in sea ice through which downward jet-like, buoyancy-driven drainage of flood water is thought to occur. 

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