https://steemit.com/steemit/@shenanigator/the-ultimate-guide-to-steemit-money
Steem power & Voting Power are 2 different things. Steem Power increases reward amount. Voting power is expressed in % (e.g.100%). It will decrease after each vote, and will recover slowly. Vote $ amount=steem power * voting power %. U can check voting power info at steemnow.com.
Steem blockchain is a well designed system. Feel free to search useful guides in steemit.com.