Sorting through all the content within an online directory can be tricky, particularly if you’re not exactly sure what you’re looking for or how it might be categorized. Fortunately, many online directories also include their own search engine. For instance, if you go to the Open Directory Project page and search for “iron chlorosis” you can find the same article mentioned above. The search function is particularly effective if you have some idea of what you are looking for, but aren’t quite sure where it might be located. Many of these search engines also allow you to narrow search results based on categories or type of content.