[Kaperstone]

pawn Код:

CMD:v(playerid, params[]) {
    new cmd[4];
    sscanf(params,"s[4]",cmd)
    switch(cmd) {
        case "lock":
        case "find":
        case "park":
    }
    return 1;
}

You can use sscanf to seperate the string entered after the command name and store it in 4 cells big array and compare the result.
check if the array cmd is null to see if the player typed in something after the command name and if he didn't,send the message "[Usage]: /v [find, park, lock, get]"