What does the blind cat Tianjin mean?

"Blind cat" refers to a cat that doesn't know how to hunt, which is a metaphor for someone or something who succeeds by chance. The phrase "a blind cat speaks Tianjin dialect" means to describe a person who doesn't know Tianjin dialect, and accidentally says it correctly when he speaks Tianjin dialect, which is similar to "a blind cat catches a dead mouse". It can also be described as someone who doesn't know much about something, but is right by accident.