Use OnClientSayCommand forward:
Code:
public Action OnClientSayCommand(int iClient, const char[] command, const char[] sArgs)
{
if ((StrContains(sArgs,"despite",false) != -1)
|| (StrContains(sArgs,"being",false) != -1)
|| (StrContains(sArgs,"only",false) != -1)
|| (StrContains(sArgs,"13% of",false) != -1)
|| (StrContains(sArgs,"population",false) != -1)){
//ban player code depends on ban system..
return Plugin_Handled;
}
else return Plugin_Continue;
}