cannot explain or find out why
Chinese idiom, Pinyin is B ù K ě Ji ū Ji é, which means it can't be asked to the end. From the popular romance of the Republic of China.
Idiom explanation
Investigation: tracing; interrogation: questioning. We can't get to the bottom of it.
The origin of Idioms
In the popular romance of the Republic of China written by Cai Dongfan and Xu Xun's father for the first time: "a good Chinese country is torn apart by this powerful group of great men. It's hard to doubt that the Republic is there."
Idiom usage
It is used as predicate and attributive.
cannot explain or find out why
difficult miscellaneous diseases - yí nán zá zhèng
learn from each other by an exchange of views - qiē cùn zhuó mó