为侦破案件而对一定范围内的人或物逐个摸底调查to investigate a range of people or objects

• 刘云平副局长沿津保公路摸排经营鞭炮导火索的摊点。

  Vice Bureau Chief Liu Yunping went along the Tianjin–Baoding Highway investigating stands selling firework fuses.

• 办案人员经过近两个月的深入细致调查摸排，获悉李永和可能已逃跑到川滇交界的金沙江边。

  Those handling the case carried out nearly two months of thorough and detailed investigations, finding out that Li Yonghe may have escaped to the banks of the Jinsha River on the border between Sichuan and Yunnan.