Unfortunately, it does not work quite like that, mate. The signal reception is limited by antennae (or aerial) design and some phones are better than others. There are copper sheets inside your phone's chassis serving as antennae and there is not a reasonable (or prudent) way to improve their capacity.
Since your phone is new, you might consider exchanging it to see if that one was somehow faulty. i have not yet heard any complaints about poor reception on that model (or any high-end Nokia, for that matter), so it may be that it was somehow damaged before you got it.
