Ranked Points Question

Hey guys, this is my first season playing ranked and i have a question about the number of points received after a victory. I started in bronze 5, and with some battling made it into bronze 4. In B5 i was getting 17-24 points for a victory and -17-21 for a defeat.

Now that I'm in B4 Ive played 6 games, 5 of them were victories and i received 9, 12, 9, 11, and 9 points and for my defeat I lost 20. I am not arguing the points awarded as much as I'm trying to figure out why the game has decided to award so little, and how can i change its mind, lol. My last victory I was 5/0/10 in the jungle, I pushed lanes, got towers and the other team finally surrendered.

I don't know if it matters but overall in ranked I'm below 500 with a win rate of 44% over 213 games. I've played much better over the last 20 games or so.

Any help understanding the system will be much appreciated.

Thanks Blacksmith