méi lái yǎn qù

眉来眼去 (眉來眼去)

eyebrows incoming and eyes outgoing

make (goo-goo) eyes at each other; flirt; exchange amorous glances

Example:

两人眉来眼去, 以目送情。
Liǎng rén méi lái yǎn qù, yǐ mùsòng qíng.
They both exchanged amorous glances which clearly made known their feelings.