隐情 (yǐn qíng): Hidden facts / Secret (Noun) — Meaning & Stroke Order

He has a hidden reason, so he doesn't want to say it.

After thorough investigation, we did not find any hidden facts related to this matter.

Given that this matter may involve personal secrets, it is advised to discuss it cautiously in the internal meeting.

This case seems simple, but after investigation, it was found that there is more to it than meets the eye.

Although he tried to conceal it, the unease in his eyes revealed the hidden facts in his heart.