Que te voy a decir que tu no sepas

[ROBINDESBOIS]

in English?

[chileno]

What am I going to tell you that you already do not know.

[ROBINDESBOIS]

sI, ya pero es una frase que se usa en inglés para abreviar una conversación o confirmar algo?

[chileno]

sI, ya pero es una frase que se usa en inglés para abreviar una conversación o confirmar algo?

Sí.

o para copuchar un poco más... :D

[poli]

I'm telling you, you know nothing:thumbsup:.(you don't know nothin'):warning:(NADA FORMAL)
You don't know diddly(parece del campo)
You don't know dick :warning:(VULGAR)
You are clueless/you are without a clue:thumbsup: (más nuevo-dicho por jovenes)

[ROBINDESBOIS]

Poli I think you misunderstood , I suppose I didn´t express myself right.

[Rusty]

"What can I tell you that you don't already know?" is a pretty common phrase that happens to be almost a literal translation.

However, I think you're looking for something like "Let's cut to the chase. (Ir al grano (http://www.tomisimo.org/idioms/es/ir-al-grano-1406.html).)" Instead of beating around the bush (dando rodeos), we get right to the point (the important matter) - we get down to the nitty-gritty.

[ROBINDESBOIS]

In faCT I was looking for "What can I tell you that you don't already know?", thank you.

can already go at the end of the sentence, somehow or other it sounds better to me.
"What can I tell you that you don't know already ?"

[Rusty]

It can go in either place. It sounds better to me in front of the verb.

[Tomisimo]

It would still be grammatical if the adverb came after the verb, but it sure sounds strange.