I recommend Mise-en-scène Perfect Serum Original.

The hair care product I use is Mise en Scène's Perfect Serum Original! It's a favorite of mine that I'm already on my fourth bottle of. After washing my hair, if I apply an amount about the size of a 500-won coin, the serum nourishes my split ends and frizzy hair, making it stronger. My hair is quite damaged from frequent dyeing, but applying it consistently has given it a shine! It's great to apply a little serum on rainy days when my hair tends to get even drier. The only downside is that since it's an oil, it feels a bit sticky when the serum-coated hair touches my face. So, before bed, I apply it to my whole head and tie my hair into pigtails, but during the day, I avoid applying it to the parts that touch my face. Mise en Scène serum is so good, so I highly recommend giving it a try.