SELECT maker, type FROM Product
WHERE maker IN
( SELECT maker
FROM
( SELECT maker, type FROM Product GROUP BY maker, type )
x GROUP BY maker HAVING count(*)=1 )
GROUP BY maker, type HAVING count(*)>1
SELECT `maker`, `type`
FROM `Product`
WHERE `maker` IN (
SELECT `maker`
FROM (
SELECT `maker`, `type`
FROM `Product`
GROUP BY `maker`, `type`
) AS `x`
GROUP BY `maker`
HAVING COUNT(*) = 1
)
GROUP BY `maker`, `type`
HAVING COUNT(*) > 1