Complex sentence: Laucke taught deLucía music by Bach and Villa-Lobos and deLucía in return showed Laucke some of the secrets of his art of flamenco, an oral tradition handed down through generations, "their secrets and knowledge jealously guarded".
Split into simpler sentences: Laucke taught deLucía music by Bach and Villa-Lobos. In return, deLucía showed Laucke some of the secrets of his art of flamenco, an oral tradition handed down through generations, "their secrets and knowledge jealously guarded".