In people's search for higher incomes from Google AdSense a lot of AdSense publishers are looking to find those keywords that really bring the best income possible. The higher an advertiser pays for a keyword, they more the advertiser receives when they click on a link.
But how can you find such words for your site? Well, the answer to that question depends a little on who you are and what you're prepared to do to get those keywords. But the general good news is that you can indeed find such words if you need them.
Of course, if you can afford such a solution, one of the best ways of getting your hands on those words would be to pay for them. There are specialized companies that do business by finding people good keywords, not only for the purpose of more AdSense revenue but for search engine optimization as well.
Such a service can be found on "Top Paying Keywords" http://www.toppayingkeywords.com/?hop=moneymkr and this is a no-brainer to getting relevant content on your site and increasing your revenue by a whole bunch quickly.
Of course, if such a solution does not work for you, you can ultimately resort to a method of personal investigation. That means you try out keywords by yourself and see which ones work better or worse for yourself.
While you might also be doing this for the first method (paying someone else to get the keywords) it would probably be better then this because you'd at least be narrowing down search to certain items.
While you're trying this make sure to keep using AdSense's 'channels' feature along the way as it can be a very good way of letting you know which sections of your site are generating income and which aren't.