pld:
Apparently it is called "Chasing Rainbows".
They posted the song on their YouTube channel ORIGINAL SONG | 여덟번째감각 | The Eighth Sense.
In the Description it says: "Special thanks to the composer Kang Yun-won, for the original song and Lee Mi-ra for performing it on set. "
Aww thank you! I really loved the singing. Wish they did a studio version too but I'm happy they uploaded the drama version with english subs!
