永远添不满的地方叫心脏
[yŏng yuăn tiān bù măn de dì fāng jiào xīn zàng]
It indicates an endless yearning or void deep inside. Hearts always want more when it comes to emotions, suggesting that no matter how much affection is poured into it, one might still feel inadequate as a metaphor for human insatiability or the depth of emotions such as love and desire for more happiness.