I would like to know what this saying means, I got the meaning that Friendship is like a river that comes clean  and goes ... I did not get the meaning, follow below:

Dostuluk iki yürek arasında akan bir nehir gibidir, gittiği yeri de temizler, geldiği yeri de.

Thanks!

Friendship is like a river that flows between two hearts, it cleans both the place it goes to and the place it comes from.