Exclude posts from search results

I am running Related Posts Pro on the test version of a new site and you can see it on the link I mention above. Ihave a simple query. I have looked in the settings and documentation but can’t see an obvious place to exclude certain posts from the results generated and want to ask if this is in fact possible? There are some posts which I do not want to appear in any related posts search results and would like to exclude them from being displayed by the plugin. Is this possible? Thanks.