How to get out of bronze league in starcraft 2?

i am so tired of playing with total noobs in bronze. it seems everytime there is one protoss i see mass voids, zerg mass mutalisks or hydralisks and terran i see lots of banshees. it pisses me off because im ranked 4 in my division with 600 points and 24 wins, i watch games online played in platinum and diamond and these people actually know how to play and dont just spam one type of unit that is a little overpowered. ive been playing since the week it came out and i originally was placed in gold but they moved me down to bronze after a couple games. ive gone on winning streaks of 7 and still i dont get a promotion why is this. i understand there is some counter thing or whatever that counts the number of times you win against certain players, how do you know who those players are and how can i get out of bronze.