The thing that you never say in aviation radio communications is "10-4". That's for CB. Roger, wilco, "no joy", and "tally ho" are used all the time. No joy means "I don't see the traffic you just told me about", and "tally ho" means "I see the traffic." This guy has a bunch of videos that are pretty good for radio comms: https://www.youtube.com/channel/UCxGjm4p2paQEhuyuVp_woDA
Thanks for the video. I did my PPL in the UK so coming to America was a bit of a radio culture shock. I think "looking for traffic" and "traffic in sight" are the ICAO phraseology, and will work everywhere. Flying to France, you might confuse a French controller by saying "tally ho".
Having thought about it some more, the statement about "roger" not being allowed was probably missing some context. He probably meant it in the context of an ATC instruction that requires reading back.
