What do you mean, not found?

Undetected means that a person or a group of people have not discovered or perceived something or a problem in the past time.

The idiom "never discovered" is often used to indicate problems or facts that have not been discovered in the past. Example: I didn't find anything wrong with the house when I bought it, and now I regret it; They didn't find any financial problems in the company, which caused great losses.

In life or work, we often encounter some problems. If we can find and solve it in time, we can avoid more serious consequences. "Discovered" reminds us to be alert to the surrounding situation, pay attention to observation, and find and solve problems in time.