Is there a "fix" way to govern your people?

I've been reading a lot about the history of Chinese emperors, their downfall, the fight within their family, etc.

Some emperor was benevolent during the first era of their rule and their empire prospers, but during the peace, their kingdom declined.

It seems to me there's no "fix" way to rule an empire. Things have to change depending on the era, "warring" era, "turmoil", and "peaceful" era.

Is there any book that talks about these things?