galactose vs sugar of milk

galactose

noun
  • A monosaccharide found, along with lactose, in dairy products, and is synthesized by the body where it is found associated with glycolipids and glycoproteins. 

sugar of milk

noun
  • Lactose, a disaccharide found in milk. 

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