search for寻找,搜寻,后面接搜寻的对象(表示搜寻的动作)
They
set out to search for the lost child.他们出发去搜寻失踪的小孩。
search out 把.......搜寻出来,找到(表示搜寻的结果)
The lawyer searched out the witness.律师找出了目击证人。
search through在.......搜寻(表示搜寻的范围)
They searched throught the neighborhood for the lost child.他们为寻找失踪的小孩搜遍了附近的区域。