It is often used in a rhetorical way to imply that the speaker is not willing to share information with someone who is not interested or who is being intrusive.
Here are some examples of how "qui veut savoir" could be used:
* "Qui veut savoir?" (said with a dismissive tone) - This implies that the speaker is not interested in revealing information and is irritated by the question.
* "Qui veut savoir ce qui s'est passé?" - This translates to "Who wants to know what happened?" and could be used in a situation where someone is asking about a personal or sensitive matter.
* "Je ne vais pas te raconter ma vie, qui veut savoir?" - This translates to "I'm not going to tell you my life story, who wants to know?" and implies that the speaker feels their personal life is none of the other person's business.
In essence, "qui veut savoir" is a short, direct, and sometimes blunt way of saying that the speaker does not feel the need to share information with someone who is not entitled to it.