1. We need to search out the truth behind this incident.
我们需要查明这起事件背后的真相。

2. The investigators are trying to search out the cause of the fire.
调查人员正试图查明起火的原因。

3. It is not easy to search out all the relevant documents.
要找齐所有相关文件并不容易。

A: We must search out the real reason for his sudden departure.
A：我们必须查明他突然离开的真正原因。

B: I agree, and we will search out every possible lead.
B：我同意，我们会搜寻每一个可能的线索。

1) 搜寻并查明

2) 找寻出

3) 调查并发现

1. 搜寻并查明

e.g. They managed to search out the missing files.
他们成功找出了丢失的文件

phrasal verb

1. To find or discover something through careful searching or investigation.

Synonym: discover, find out, uncover