Working with Mail
Say you store a group of related messages � the original as well as any replies and forwarded messages � for record keeping. Eventually, you may want to purge these messages. Rather than searching for and deleting the messages one by one, you can quickly group them, then delete the group.
To do this, switch to the folder that contains the messages. Select Current View from the View menu, then By Conversation Topic from the submenu. Click the header for the group you want to delete, press the Delete key, then click Yes to confirm the deletion.