Interactive commands with pipe and grep

There are commands such as top, watch, Airodump-ng, etc, that whenever you run, everything on the terminal change all the time. What I want to do is that run one of theses interactive command and then use pipe to grep something I've been looking for. Take this for instance: airodump-ng wlan0 | grep "QQ:AF:00:55:8C:DF" In this example I am looking for a MAC address, when this MAC turn up, it will appear on screen so that I can grep it. The problem is that it doesn't work. I have searched a lot to no avail.