The advice I just gave is more valuable then you could ever imagine.
There is no way for anyone one here to know what you have already done. Have you done keyword optimization? Are you targeting one word or many? Are they related words or are running a general site? Are you looking to do white hat or black hat SEO, you'll notice there is a section for each on here.
You're asking everyone on here to basically fix your car, when you haven't told anyone what kind of car, what the problem is, or if you even understand how your car works other than it's not doing what you want...