pick over something
phrasal verb with pick verb uk/pɪk/ us/pɪk/
挑拣;甄选，精选
to look carefully at a group of things, choosing the ones you want or getting rid of the ones you do not want
All the clothes at the sale had been thoroughly picked over and there was nothing nice left. 所有削价销售的衣服都被别人仔细挑过了，没剩下什么好的了。