Well…explain please…
Martial Joe
That’s for you to figure out. Watch some boxing matches.
Your wrong,I wont waste my timetrying to see wing chun in boxers when i watch a boxing match…
on speed
i’m not very powerful right now as I hardly have time to practice anymore, and I haven’t touched a heavy bag in ages 
but I’m still very fast. To get fast, you utilize Wing Chun’s concept of “tan ging” where the limbs are relaxed until the moment of impact. This is true for both hands and feet, blocks and attacks. I’ll use the hands to illustrate my point:
for say a punch, keep the hand open and relaxed as you begin to punch. Only close into a fist right before impact.
In the case of blocks, the motion is whip-like, sort of like when whipping a towel in a changeroom. An example is how the biu sau is supposed to be executed.
To get fast, you must also train chi sao with an opponent trying to score multiple hits on you. that way you learn to block fast or get hit. And to train attacking speed, get an opponent who can block most of your hits so you have to work faster to get one in. This is why training with an opponent better than you is important to improvement.
You must also practice air blocks, air punches, and simultaneous air punches and blocks.
That’s how you develop speed. The ability to use your strength to it’s potential is called power. This must be developed through air punching and sandbag punching. When punching the sandbag, don’t merely aim at the bag but aim at the wall behind the bag. Aim to punch through the bag, so you don’t “stop-short” and pull your punches just at the surface.
Hope this helped.
Quickness
first train the correct technique. do them slow until you get it right. Speed comes from repetition. Do techniques hundreds of times and concentrate on form. Then you add power by thrusting your hips and the correct footwork