Using Webmaster Tools (Google or Bing), you can try to figure out what your top blog articles are or should be. You can also drive yourself crazy. People search for all kinds of random stuff, and some of those searches might put you in a top search position, but that doesn't mean you need to continue writing articles about that topic. On the other hand, you might get very little attention for some other article you wrote, probably because a lot of people are trying to cash in on the search. Let's take a look at a recent Google search result for one of my local Jacksonville, FL, blogs.
I'll talk about some of the searches and articles, but others will confound me. About 20 of these are top 10 of Google. And it changes monthly, so that's weird. If you scroll down, you can get an idea how the searches work, with similar phrases coming up. When you write your own content, take a look at something like this, and then write so that the search terms you want are represented in the articles. If nothing else, it can help you decide your next article for that site, like what's missing from the list.