The search option from the Action menu will bring up a search window. There are a number of search criteria to choose from.
The search currently does not allow wildcards.
Double-clicking on a search result item will move the calendar to show that item and open the appointment editor for the day containing the item.
You can perform bulk deletes from the search screen. There is a menu option to delete selected items. You can select multiple items and then use the menu option to delete them all at once. This is a good way to clean up old appointments that are not needed.
You can also change the category of multiple appointments at the same time.