[DarkSkull]

PHP код:

new blocked[][] = {
    "php","html","java"
};
Checkwords(string[]) {
    for(new i = 0; i < sizeof(blocked); i++) {
        if(strfind(string, blocked[i], true))
            return true;
    }
    return false;
}
if(Checkwords(text)) {
    Error(playerid, "text not allowed.");
} 


Try this. Just add more words to the array.

EDIT: I have edited the code. Try that