If your TV has no 'Menu' button on its front panel controls, it will be difficult to make an auto-tune to it. Anyway, try to enter its 'Menu' option, using the remote control you have. If can, you will win. Otherwise, buy an other universal remote control, which will help you to enter the TVs' Menu option. The one more thing you have to try is, to set an other code to your TV with this remote control. If it too do not help you, think of buying an other remote control.
If you wish to buy a genuine remote control, you have to contact the authorized service center. If you wish to buy a universal remote control, you should know about, which brand remote control have set-up codes to your TV brand, and buy that one according to availability. The first thing you have to do is, to confirm the number of digits in the setup codes to your TV brand. There are 4 digit, 5 digit, 3 digit and even 2 digit codes. You can make it sure by entering '0s' at the code enter window the TV dispays, and asks codes. Enter 'Zeros', and count how many zeros can be enterd. That number will be the number of digit of setup code, the TV/Device need. If you can enter 5 zeros, the number of digit in the set-up code to your TV is a '5' digit one, if only 2 zeros can be enterd, the number of digits in the set-up code to your TV should be a 2 digit one, and so on.. If you wish to get more details about this, try the sites linked here.
Both the sites have setup code list, and setup procedure to many popular brand remote controls. Check the site in 'Mosaic
' view. It will make search easy.
It will be preferable to buy its genuine remote control by any way.