contemplation vs soul-searching

contemplation

noun
  • The act of contemplating; musing; being highly concentrated in thought 

  • The act of looking forward to a future event 

  • Holy meditation. 

  • The state of being considered or planned. 

soul-searching

noun
  • Probing introspection; a critical consideration of one's conscience; also, an instance of such consideration. 

adj
  • Involving probing introspection, or a critical consideration of one's conscience, especially motives and values. 

How often have the words contemplation and soul-searching occurred in a corpus of books? (source: Google Ngram Viewer )