cruller vs pirozhki

cruller

noun
  • A donut in the form of a twisted ring. 

pirozhki

noun
  • A single such pastry. 

  • Small pastries filled with finely chopped meat, vegetables or fruit baked or fried, from eastern European cuisine, or a serving of these. 

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