The combination bet combines several bets with each other. In this case, all bets must be won for the combined bet to be considered as won. The bet must combine at least two bets, the provider can set a limit. With most betting providers, combination bets of up to 10 different bets are possible. With this bet it is possible to win a lot of money with a small stake, but this also carries a high risk, since the money is gone if only one of the bets is lost. Source: https://www.betting.org/betting-tools-software/arbitrage-betting/
Multiple combination bets can be combined in the system bet. In contrast to a combination bet, a win can still be made with one or more incorrect results. An example is a 2 out of 3 system bet. Here 3 bets are placed, in 2 games won the player has already made a profit. The bet amount is slightly higher here, since each system bet consists of several single tips.
If you are sure that one team will lose, but you cannot tell whether the game ends with a draw or with a victory for the other team, you can place a returnable bet. Here you have the possibility to place two different bets and bet on both results separately. This increases your chances of winning.
As the name of the winning bet suggests, you bet on the winner. If the winner is correctly predicted, the bet is considered won.