You might have used different kinds of tools to spy on your competitors. There must be some manual or automated analysis paid or free tools, in terms of getting the list of the keywords of your competitors that that they are using. It is all the part of competitor analysis. But, the things in which google percieve things, in order to rank a website is completely changed.
One of the seo techniques or seo tool that I am going to introduce, to know on what keywords a particular website is ranking in even the top 5o's. The tool is known as spyfu, just click below and check yourself by entering the competitor's url.
There must be a number of instances when you want to know the varied keywords of your competitors focusing on ranking in the top search engines. You might have got some from the keywords in meta tag or title tags. But, still there are keywords which must be beyond your ken. Spyfu gives you the full control over spying the competitors keywords randomly, not just they are using in only title and meta tags, but much more than that.
So, what are you waiting for spy on your competitors. I'll be back with some more interesting tools.