"Os jovens que a gente tem encontrado não entendem um texto."
This English sentence is very strange, largely due to "a text" being present.
On a previous variation of this text, "we have found" was not accepted. They wanted, "we have been finding". The alternate correct solution given here has, " we've have been finding" which has the "have" in two forms. Also I am wondering if the meaning might be intended that the youngsters, "do not understand even one text".