You can also try:
query1:
SELECT c.name, c.email, o AS orders, w AS wishlist
FROM Customer c
NEST Orders o ON KEYS c.orders
NEST Wishlist w ON KEYS c.wishlist;
query2:
SELECT c.name, c.email, o AS orders, w AS wishlist, d AS documents
FROM Customer c
NEST Orders o ON KEYS c.orders
NEST Wishlist w ON KEYS c.wishlist
JOIN Documents d ON KEYS c.documents;