is there any buttons on laptops to make wifi signal stronger?

ive recently bought a laptop from comet, i had a massive problem with it freezing.. no signal from my router unless it was sitting next to it, a bluetooth button but no bluetooth, and a the scroll button on the side of the touch pad is not that sensitive. i went back to get it either swapped or my money back. they said they couldnt get me my money back unless they tested it proppley.... there had been so many problems from the onset that i just wanted to swap it. anyway aftera non responsive talk to the guy, i agreed to let him test it. He said the internet connection was fine, and he did a factory restore to even out any glitches. ive sinse taken it home... most of the problems have been sorted but it still the internet only works when it is sitting next to the router. im so angry as £500 dosnt come easy and despratley need to internet to connect propley.... and no its not a problem with my internet as we have 2 comps running off it with no problem at all

help!!!