Advanced searching provides additional ways to find information and can help you narrow your searches for more precise results.
Microsoft HTML Help: If you are creating a Microsoft HTML Help project, you need to include a Search tab (this tab is selected by default) and enable advanced full-text search. You do this by customizing the HTML Help viewer. From the Search tab in the HTML Help viewer, users enter (or select) the Boolean and wildcard expressions with their search criteria. Microsoft HTML Help also enables users to search previous results, match similar words and search only topic titles.
WebHelp: If you are generating WebHelp output, you need to include the Search tab (this feature is enabled by default). Advanced searching is built into the search functionality. From the Search tab in the browser, users enter the appropriate Boolean expression (such as AND, OR and NOT) for enhanced searching.