In my native language, we have this proverb: when an ox cart is turned over (or turns over) only then one will see the road

The closest thing that I can think of would be the fairly common expression in English hindsight is 20/20:

In hindsight, things that are obvious now were not obvious from the outset; one is able to evaluate past choices more clearly than at the time of the choice.

Quite obviously, it's not the exact equivalent, but conceptually the two expressions are really more or less the same. To get a better idea how this idiom works, take a look at this example:

With 20/20 hindsight, it's now obvious that we should not have trusted this charlatan from the very beginning! He cheated us out of all our money!

a rude awakening TFD

The shocking instance of learning the unpleasant or unwelcome truth about a situation.