게 팔리다

sell like hotcakes

팔리다 is the passive of 팔다 — goods being sold rather than someone selling them — and -게 gives the manner. Four of the five lines here use 불티나게, literally 'like flying sparks', which is the set idiom for selling out fast; the fifth is the plainer 빠르게 팔리는 상품들 (fast-selling items). If you are the seller, use 팔다; 팔리다 describes the goods.

Register: neutral; 불티나게 팔리다 is a set phrase