Range on CB is usually VERY close....like a couple miles tops. On that radio, if you're using the supplied rubber duck antenna, you won't get much at all...that antenna is not well suited to 11 meter CB...literally that's the very bottom of the supplied antenna's range, and it's certainly biased toward much higher frequencies anyway.
MAN means you're in manual mode instead of scan. SR1, is a search range, not a scannable bank..., you're kind of scanning, since it's a defined range and only 40 frequencies, but not really 'scanning'.
If you were sitting in a truck stop parking lot (not really advised for the uninitiated) you'd probably hear something, and it would probably be unsavory.
I put CB channels in a bank in my 162, and scan them during my commute. Search ranges are a pain unless you're sitting still, and CB is 99.99999% a mobile activity.