What did Jesus study as a young man in Egypt?

The christian bible has does not mention what Jesus was doing from about the age of12 to about 27-30. However there are stories in other traditions, Jewish, Islamic, Ebionite and other non-christian Jesus movements. One strange story that keeps coming up from widely diverse sources is that Jesus went to Alexandria in Egypt and studied or meditated at an Egyptian Temple there, and demonstrated widely what he had learned when he returned to Judea Some of these sources say he learned to speak Greek there from the Greek speaking Jewish diaspora in Alexandria. There were many temples in Alexandria at the time but the cult of Isis had been particularly resurrected by the occupying Romans. Historians have often pointed out the similarities between the Isis/Osiris cults and Christianity ( death resurrection of god) also Isis is archaetypically identical to the Christian Madonna. Does anyone know any more about this? ^..^