With accent marks:
От добра́ добра́ не и́щут.
They do not seek good from good.
Few people know that this is only part of the proverb. Its full version sounds like this: "От овса кони не рыщут, а от добра добра не ищут" (Horses do not roam from oats, but they do not seek good from good). It means that if the horses are fed, they will not run away. If a person is doing well at home, he will not leave the family.
In its shorter version the proverb acquired a second meaning: when doing good to people, one should not expect the same from them. You need to do good selflessly.
Other Russian proverbs
Beast runs towards the hunter.
The best is the enemy of the good.
Time for business, an hour for fun.
There are no friends for taste and color.
Be patient, Cossack - you will become an ataman!
Water wears away a stone.
With whom you are friends with, from them you will learn.
Poor people are inventive.