First check the front-panel settings of your radio:

Turn the squelch control all the way down. If your radio has an RF Gain control, turn it all the way up. If your radio has a Dynamike control, turn it all the way up.

Your radio is now adjusted for maximum range.  You should be hearing background static.  To stop the static, slowly turn up the squelch just until the static stops.

If you are still having problems, then the next step is to check the SWR of your antenna and make sure that it is below 3.

If the SWR is good and you are still unhappy with the range, then installing a longer antenna should help.