semolina vs wheat flour

semolina

noun
  • Coarse grains produced at an intermediate stage of wheat flour milling. 

  • Such grains, usually from durum wheat, used in the preparation of pasta, couscous and various sweet dishes. 

wheat flour

noun
  • Flour made from wheat. 

  • exact synonym of flour 

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