Hello!

The literal translation of the Fuzhou dialect you are talking about is stinky fish in Mandarin. It seems that there is no such fish, but this expression is used to describe someone who is reckless, stubborn and reckless. Some people also say pinch the blind jade (blind fish) or pinch the jade (bonito fish), which is a metaphor for recklessness and rampage, like a blind fish.

Cao Lao Yu may also be a homophonic pronunciation of "Grasshead Fish". In Fuzhou dialect, "第拉玉" means grass carp. In Fuzhou dialect, it is 第(cuǒ)yu or 第(cuǒ).

For reference.