rumination vs soul-searching

rumination

noun
  • Deep thought or consideration. 

  • The act of ruminating; i.e. chewing cud. 

  • Negative cyclic thinking; persistent and recurrent worrying or brooding. 

  • An eating disorder characterized by repetitive regurgitation of small amounts of food from the stomach. 

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 rumination and soul-searching occurred in a corpus of books? (source: Google Ngram Viewer )