心若相知无言也默契情若相眷不语也怜惜
[xīn ruò xiāng zhī wú yán yĕ mò qì qíng ruò xiāng juàn bù yŭ yĕ lián xī]
This means that if two people really know each other well enough in hearts, no spoken words can still communicate and understand each other deeply; and even without verbal expressions of love, the bond remains tender.