Hey BeeBee. The requested Network Unlock code is specific to you phone. To find it out you will require certain special equipment the procurence of which is only cost effective if so done for commercial reasons. The two alterantives/options you have are (please note that each method will cost you money):
1. Contact the carrier to which the phone is currently locked and ask to be assisted with the unlock code (they will tell how much you will have to pay).
2. Or purchase an unlock code from sites like sim-unlock.com - here is the V795 link http://sim-unlock.net/simlock/ZTE/Kis_II_V795/