To search for content, go to the Content Overview page and use the filter at the top.
Filter by content type, and then if it's published or not. When finished, use Reset to go back to the default view, or to start a new search.
This search can be useful, for example, If an event repeats once a year, and you update it, instead of creating another event.
Events can be configured with repeating dates - for example: The 4th Monday of every month. If one of those repeating dates falls on a holiday, you can remove that Instance. This video will show where to find the list of repeating dates, and how to manage that Instance. Just delete the instance and save, and that day will be skipped on the calendar. (In the video I do not actually delete it, because it's in use.)
Note- the Calendar will display one year of repeating dates at a time.