You can't connect a resistor in parallel with them to limit the current. When components are in parallel the voltage across them is the same, but the current could be anything.
LEDs need a certain current to light, not a certain voltage. Your LEDs are rated at 0.03 A, so that is what you should provide. You will have to supply around 3 V to each one, but it might be a bit more, it might be a bit less. As you found, you will not get the right current if you connect them to a 3 V supply.
The easiest thing to do is to put two LED in series, with a 220 ohm resistor in series with both, and connect that lot to a 12 V supply. If you want more than two LEDs, you can make up as many groups, each with two LEDs and a 220 ohm resistor, as you want. Connect them all to the 12 V supply.