Depends which brand/size they are. I boost the range of my wakie talkie by making an in-line amplifier, because you need to increase the wattage. This increases the range conciderably but take into account that the antena will most likely need to be changed to handle the power change. If you can get the scematics you should be able to find where to put the amp. Check the legal limit of watt output you can have due to crtc limits.
