brooding vs heartfelt

brooding

adj
  • Deeply or seriously thoughtful. 

  • Broody; incubating eggs by sitting on them. 

noun
  • A spell of brooding; the time when someone broods. 

heartfelt

adj
  • Believed or felt deeply and sincerely. 

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