Ask too much to get enough.
More Spanish Proverbs:
A handful of motherwit is worth a bushel of learning.Spanish
Love one that does not love you, answer one that does not call you, and you will run a fruitless race.
Spanish
Don't kill the man at the count's desire.
Spanish
Whither shall the ox go, where he will not have to plough?
Spanish
Be my enemy and go to my mill.
Spanish
Sloth is the mother of poverty.
Spanish