“Chá”(tea)has the same sound of “Xá”, that stands here for the imperative of the verb “deixar” (deixa!). Deixar means to leave in this case (and can mean to let, to permit, to allow in others).

A few words about this: the correct imperative in this case is “deixe” and not “deixa” (deixe is the imperative for tu (thou) and not for você (you): deixe tu, deixa você. Thus, “DEIXE que eu livro a TUA (thy) cara” or “DEIXA que eu livro a SUA (your) cara”), so it is a very colloquial use. Besides, we are known for omitting some sounds, thus “deixa” becomes “xa”. Following the acent marks rules, “xá”. Someone came up with the “chá” thing to make fun out of Globish (see below).

“Livro” in this case stands for the verb “livrar” (to free, to release, to save, to rescue depending on the context) in the present simple tense (presente do indicativo). Eu livro, tu livras, ele livra etc… and not for book, although the words are the same. This is due to Latin (liber, libri for livro / liber,a,um for the verb livrar). Portuguese is a Romance language after all.

So, the phrase is really “Deixe(a) comigo que eu livro a sua cara”. And no safe and sound Brazilian would do such a translation involving tea and book. That’s a joke about some language courses in Brazil that promisse someone can “be fluent in English in 8 weeks”, what is obviously impossible.

Correct, proficient Portuguese is really not that simple.

“Chá” é uma corruptela do verbo “deixar”, e não “tea”.

“Livro” é do verbo “livrar”, e não “book”.

“Livro” traduzido como “book” ?
O correto é traduzir como “free” ou outro verbo com significado similar.