scour 2 
(skour)
v. scoured, scour·ing, scours
v.tr.1. To search through or over thoroughly: The detective scoured the scene of the crime for clues.
2. To range over (an area) quickly and energetically.
v.intr.1. To range over or about an area, especially in a search.
2. To move swiftly; scurry.
[Middle English scouren, to move swiftly, probably of Scandinavian origin; akin to Old Norse skūr, shower.]
scourer n.