The correct term is "Checkmate," not "Czech mate." "Checkmate" is a term used in the game of chess to declare the end of the game when the opponent's king is in a position to be captured (in check) and cannot escape capture on the next move (mate). In chess, the objective is to checkmate your opponent's king, and once this happens, the game is over, and the player who achieved checkmate wins.
The phrase "Checkmate" has also been used metaphorically outside of chess to indicate a decisive victory or a situation in which someone is defeated or outmaneuvered in a contest or conflict.
It's possible that "Czech mate" is a pun or wordplay, but the correct and standard term is "Checkmate" in the context of chess and its metaphorical use.