heartland vs within

heartland

noun
  • The central part of a region defined by geographical or non-geographical criteria, such as support for a political party, faith or similar. 

  • The part of a region considered essential to the viability and survival of the whole. 

within

adj
  • In the context of which the present document or ruling is made. 

adv
  • In or into the interior; inside. 

prep
  • Before the specified duration ends. 

  • In the inner part, spatially; physically inside. 

  • In the scope or range of. 

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