От добра добра не ищут.
Is its meaning the same as in
Лучшее - враг хорошего?
If not, are there any similar idioms in Russian which might clarify the meaning of the former phrase?
I would say that they have roughly the same meaning with some nuances.
"От добра добра не ищут" usually refers to a complete change, which is too risky (such as changing job, place of living, place of studying, citizenship, changing the key elements of business such as personality of the management, market target, basic design and so on)
"Лучшее враг хорошего" usually refers to to minor improvements which may be good taken separately but have tendency to never end because of newer and newer ideas appearing and hamper normal production process. This may also refer to never-ending reconstruction and other pursuits for perfection.
Нет, это не совсем одно и тоже.
Лучшее - враг хорошего - не сто́ит пытаться улучшить/доработать что-то, что уже работает хорошо. Чаще применяется к материальным вещам/процессам/технологиям, на которые можно легко повлиять и легко испортить, получив результат, обратный ожидаемому.
Yes, that was precisely the interpretation* by Leo Tolstoy: he even wrote a short fable to illustrate it:
Бежал заяц от собак и ушёл в лес. В лесу ему хорошо было, да уж много он страху набрался и хотел ещё лучше спрятаться. Стал искать, где поглуше место, и полез в чащу в овраге — и наскочил на волка. Волк схватил его. Видно, правда,— подумал заяц, что от добра добра искать не надо. Хотел лучше спрятаться и вовсе пропал. (Л. Н. Толстой)
A rabbit ran away from a dog, and hid in the woods. He was safe there, but because he was scared so much, he decided to look for an even better hiding place. He ran into the thickets in the ravine, and got caught by a wolf. That's when the rabbit understood that one shouldn't try improving what's good: he wanted to hid better, but got caught instead.
Pushkin's well-known "Видел я трех царей ..." quote suggests that his interpretation has been identical to that of Tolstoy, that giving up what's good in exchange for what you perceive to be even better may carry significant risks. This meaning is close to "Лучшее - враг хорошего", which translates as "Perfect is the enemy of good", though it is not entirely the same: it implies that the current state is definitely not perfect, and that it does not address the risk aspect of searching for the perfection, which may or may not exist.
I would not agree with other interpretations. You should first understand what is
искать добро. Which is similar to
seeking the truth. Now
от добра is different and means
having happy life,
having full house of goods. So comfort living will not make you the truth seeker. This may confuse if you think that
добро is used in same meaning twice, which is not exactly so. The context is normally mildly negative. It's like accusing someone (or self) of being lazy in a fancy philosophical way of saying.
I just realized you can say
with goods you won't seek for good in english.