At the beginning I had problems as well but with healing bandages, accumulate approximately 13,000.
At the end I take the option of random numbers.
I go to RANDOM.ORG - True Random Number Service website and use the calculator to generate numbers from 1 to 8.
I'm not complaining, I've won until permanent weapons. Something interesting to note, is that there are awards on corners, 1, 4, 5 and 8 cards numbers. But I repeat, everything is a matter of luck.