It's often used in a negative sense, implying that there's something you're keeping secret from someone.
Here's a breakdown:
* Que: This is a conjunction, meaning "that".
* no: This means "not".
* le: This is the indirect object pronoun meaning "to him/her".
* cuentas: This is the verb "to tell" in the second person singular, present tense.
Examples:
* "Hay un secreto que no le cuentas a nadie." (There's a secret that you don't tell anyone.)
* "Tienes un amigo que no le cuentas tus problemas." (You have a friend that you don't tell your problems to.)
It's important to note that the phrase is often used with a negative connotation and implies there's something hidden or being kept secret.