* It's a misspelling: There might be a typo. Perhaps you meant "ça va bien" (French) which means "I'm doing well."
* It's a regional or dialectal expression: Could be a specific phrase used in a particular region or dialect that isn't widely known.
* It's a made-up phrase: Sometimes people create their own expressions, particularly in creative writing or online communities.
To get a better understanding, please provide more context:
* What language are you asking about?
* Where did you encounter this phrase?
* What was the context of the conversation?
With more information, I can help you determine the meaning of "caes bien."