둘러보다 is taking in a place by looking around it — a shop, a market, an exhibition. The adverb here is nearly always about ease: 편하게 둘러보세요, the standard shop line meaning 'feel free to look around', plus 여유롭게, 자유롭게 and repeated 이렇게. There is no buying implied, which is why the shopkeeper uses it to put visitors at ease.