flapjack vs flatbread

flapjack

noun
  • A bar made of (though not limited to) rolled oats, butter, golden syrup, and brown sugar, baked in a tray. 

  • A pancake. 

flatbread

noun
  • A thin, flat bread, often made from unleavened dough. 

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