skip tracer
noun [ C ] US informal uk/ˈskɪp treɪ.sər/ us/ˈskɪp ˌtreɪ.sɚ/
（尤指以追债为目的的）寻人调查员
a person whose job is to find people who have disappeared, especially people who owe money
It's not difficult for private detectives, debt collectors, skip tracers, and creditors to find out how much people earn. 对于私家侦探、讨债人、寻人调查员和债权人来说，要想知道人们的收入情况并不难。