It depends what kind of game they are playing. If they play about dice, then luck is the only way to win the game but in cards it needs skills to win the game. Strong feeling is similar to say that we/you will be lucky within that day IMO.
I think all gambling games depends on luck, without luck, we cannot win. and it is not just for dice games but also on the other games. positive thinking only helps us at the beginning of the games and when we lose then I don't think that positive thinking will stay with us. we can lose positive thinking too besides losing our money because when we lose, we are thinking about how we can recover our losses but unfortunately, we cannot do this because we don't know if our luck still stays with us or not.