shy person vs sweetheart

shy person

noun
  • shy person 

sweetheart

noun
  • A female member of a college or university fraternity. 

  • A person who is always very kind. 

  • A person very much liked or loved by someone, especially when both partners are young. 

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