The Efficient Related Posts plugin for WordPress automatically finds related posts and posts them at the bottom of your article.
The way it finds related posts is by the use of TAGS.
So all you need to do is enter simple TAGS into your post. Make them simple keywords and NOT long sentances so that the system can find a related article. If you put in a sentance, it trys to find that exact sentance and the likihood of having that exact sentance in a post is, well, not so good right? So keep it simple okay! Use one word keywords in your tags or even just the full name of individual and the correct related posts will show up.
see images below for visuals
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