This window does just what it promises - shows the content that you are searching for. You can choose what modules are allowed in the search results. This way you can create separate search pages for you articles, products or videos.
Remember that Calendar module records are very short. If you want a longer version of an event description you can always attach an article to a specific event. It can be a news article from your news feed or just a special article you wrote to make a story about what is gonna happen.