HT12E and HT12E both have 8 bit address. so you can assign 256 different address to chips. and with one transmitter you can pair 256 different receivers. but in that case you have to everytime change address of HT12E to pair with other HT12D
for assigining address either connect A0-A7 pins to Vcc or ground. each pin can be connected to either Vcc or ground. it is not necessary that all pins should be connected to either ground or Vcc.
but at the receiving side make same pattern for A0 – A7 to match address.