This edition of the PHP Manual includes an advanced full text search possibility provided by the viewer application. This enables users to search through every word in the help file to find a match. For example, if a user does a full-text search on the word "Apache", every topic that contains the word "Apache" will be listed. Advanced full-text search allows a user to search using boolean, wildcard, and nested expressions. A user can also limit the search to previous results, match similar words, or search topic titles only.
The usage of the search feature is fairly straightforward. Click on the search tab, type in the desired words and press ENTER (or click on "List Topics"). Then you'll receive a list of matches from the PHP Manual (and the notes). You can use the button with a right arrow on it to add boolean operators to your search (or you can type them in). As you see the results, you can use the column headings (Title, Location and Rank) to sort the topic list. The default order is by Rank. You can also adjust some parameters at the bottom of this tab.
The words found are highlighted on the current page in the Topic pane by default. You can turn off this feature by choosing the "Search Highlight Off" menu item in the Options menu. To can get this feature back similarly. If you are viewing a long topic, only the first 500 instances of a search word or phrase will be highlighted, due to a limitation of the viewer.