Conversation so far:
WHICH MUSIC IN HE INTERESTED?
Greek.
IS HE WON AWARD?
CANNOTANSWER.
WHICH COUNTRY HIS GROUP BECAME POPULAR?
In 1971, some jam sessions with a group of musicians in London had resulted in two albums' worth of material.

Question: WHICH ALBUM FAMOUS IN EUROPE?
Self-contained rewrite: Which of Vangelis' albums were famous in Europe?