Complex sentence: Alves moved to his first major team, Boavista FC, for the 1974--75 campaign, where he first showed more of his talent, earning him a transfer to Spain's UD Salamanca, where he remained two more years.
Split into simpler sentences: Alves moved to his first major team, Boavista FC, for the 1974--75 campaign. The two seasons at Boavista earned him a transfer to Spain's UD Salamanca, where he remained two more years.