待心重返深海才懂深情难猜
[dài xīn zhòng făn shēn hăi cái dŏng shēn qíng nán cāi]
Translates to 'Only upon the heart's return to the deep sea does one understand that deep feelings are hard to fathom.' This implies that true understanding of profound emotions comes from introspective journeys into one's depths.