If Search in module(s) is selected, search dialog is displayed. Any selected documents from the left pane are preselected on the choose modules tab.
If Reset Main Index is selected, the Main Index in the left pane will be rebuilt. Any customization in the main index and bookmarks will be deleted.
If Remove selected item is selected, any selected items in the Main Index in the left pane will be deleted. This action can only be partly undone by the Reset Main Index. Use this feature with caution.