Hydrating serums draw water into the skin for a smoother, bouncier look and suit every skin type, including oily skin. Apply to damp skin and lock in with a cream. Popular picks include Anua 7 Rice Ceramide Hydrating Barrier Serum, Anua Birch 70 Moisture Boosting Serum and Anua PDRN 100% + Hyaluron Serum.