One of the key features for the view new content search is to set it up correctly in your profile settings. To do this go to your profile and click onto the settings tab. In the main window you will see a section called Search Settings. In the drop down box select Show me all content that I have not read. Click save changes.

This means that whenever you do a view new content search, you will see a list of all the topics you have not read. If you want to clear the list then you can select mark all items as read from the search results window