It may come as a surprise but we haven't got a magic wand you know.

All we would do is search the web in the same way you would. The only real difference is that we have a little more experience.
Not every model of every brand can be hacked by simply inputting some specific key sequence from the standard remote. Some need a service remote which uses a different set of IR codes. Others can be hacked only with a firmware update via USB or disc. Then there are those that can only be hacked with a hardware chip. Finally, there are those that can't be hacked at all.
It would appear that there's no simple user-handset hack for your player. You could try searching for LG models from the same range and year of production (Google is your friend) to see if by chance the same code works for you. If it does, then do the decent thing and post in one of the hack forums or web sites that you have had success. Much of what you see on these sites is because people just like you try various hacks and report back when they have success. So, do likewise and help the community