expert vs guidance counselor

expert

noun
  • A person with extensive knowledge or ability in a given subject. 

  • A player ranking just below master. 

adj
  • Extraordinarily capable or knowledgeable. 

  • Characteristic of an expert. 

guidance counselor

noun
  • A school counselor. 

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