If you are referring to FRS or GMRS type radios, 2 miles is just about the maximum distance you will get out of them on normal terrain. Many of these types of radios will advertise claims of 10-15 or more miles of coverage. This type of "theoretical" mileage rarely if ever occurs in typical conditions. Many factors such as trees, buildings, hills and other "line of sight" obstructions will greatly reduce the effective range.
Downloading the manual will now make the batteries charge?
Any micro USB, or take out the batteries and use an external charger.
This is more for "mshtexas" than the OP but I'm sure there may be others out there wondering the same thing. The power cord that comes with this unit has a 9.0v output at 200mA with the center pin being positive
u can use a phone charger as long as the jack is the same as your jack, walmart has about any kind they make.
You didn't include the model number of the radios, but I suspect you're referring to Family Radio Service (FRS) / General Mobile Radio Service (GMRS) two way hand held radios. The FRS /GMRS types are limited to just 1/2 watt. Base GMRS type radios are limited to 5 watts. FRS is limited to Ch 1 - 14. Ch 15 - 22 are GMRS only, and require an FCC license to transmit. You can read more about FRS on Wikipedia.
Many FRS / GMRS two way radios claim incredible distances on the packaging. I've seen some that claim 15+ miles. Given the low power (.5 watt) that they are limited to transmitting, claims such as those would be under the most optimal of conditions. I can assure you that you or I would never encounter those conditions unless we were in some sort of radio laboratory / testing space designed to obtain these crazy distances. In other words, even in optimum "real world" conditions; these radio should only be expected to work when separated up to only several "unobstructed line of sight" miles (such as across open water of a lake, along a beach, etc. The range of these same radios will be reduced significantly when operated indoors, outside between buildings, where blocked by rocks, trees, metal, etc. The only reason you may have reduced range could be due to a power level selector switch that has been set to reduce the output power of the radio. Other than that, I think you'll find a couple of miles is about all you're gong to get.