Сговорна дружина, Планина повдига

zgovorna druzhina planina povdiga

A united team can lift a mountain.

If you work together, you can achieve more than if you worked alone.

сговорна -/zgovorna/ – united or conspired
дружина -/druzhina/ – party or company
планина – /planina/ – mountain
повдига – /povdiga/ – to lift

United we are stronger is a proverb in English that has essentially the same meaning.