Ah, Oleg, based on your comment, the translation should be "If you can count to ten, count to three." I understand now what the proverb is supposed to be saying. It is definitely not a proverb I have ever heard. However, I now understand the idea completely. I feel like there is probably an equivalent proverb in English, but if so I can't think of it.
Maybe the proverb comes from a specific ethnic group.