Do you mean that you cannot see them on your marketwatch? If yes go to the marketwatch window then right click and select show all, also note that oil, wheat usually are presented with symbols depending the period.
There are many brokers who do not provide all the commodites at thier MT4 platform, so its better you change your broker and find the one you have a number of LP associated with. Also try for some other platfrom than MT4.
i was also going through the same. but i must tell you there are lot of better platrforms than MT4 in this lucarative world of forex.