scour  
verb uk/skaʊər/ us/ˈskaʊ.ɚ/
  (CLEAN)      
  [ T ] (also scour out)擦,擦净;刷,刷掉 
to remove dirt from something by rubbing it hard with something rough
  You'll have to scour out those old cooking pots before you use them. 这些旧锅用之前得好好刷一刷。 
   (SEARCH)      
 [ T ]认真搜索,细查 
to search a place or thing very carefully in order to try to find something
  The police are scouring the area for the missing child. 警方在这个地区四处搜查,寻找失踪的孩子。 
 I scoured the shops for a blue and white shirt, but I couldn't find one anywhere. 我跑遍商店想买一件蓝白相间的衬衫,但却怎么也买不到。 
 Phrasal verb   
scour something out 冲刷出;磨出
to make a hole by a movement that is repeated continuously over a long period of time
  The fast-moving water had scoured out a channel in the rock. 急流在岩石上冲刷出一道凹槽。