Rankling in, or swelling, the heart.

soul-searching

plural of heartsearching

plural of heartseed

plural of heartsickness

In a heartsome manner.

plural of heartscape

A notional landscape of the human heart or emotions.

plural of heartsong

(obsolete) A heartwarming song or poem. / A song or message that is deeply heartfelt. / The expression of a person's inner essence, underlying identity, and reason for existence.