For instance, I believe there's a series of simple actions I could undertake - speaking to people and so on - that would make me very rich, or powerful, or very well-connected. There is certainly nothing physically impossible about it. But I have no idea how to locate the concrete series of actions in the huge space of my physically possible actions.

Buying the right lottery ticket is would be a perfect example. Unfortunately for us, there's no practical way to know what the right one is. ;)