You can unpublish (i.e. hide) a chapter so that end users cannot see the content. This article will teach you how to make an unpublished/hidden chapter visible to your end users in your manual.
Unpublish the chapter
Upon unpublishing a chapter, you'll be given the option to either unpublish all of the articles in the chapter at the same time or to just unpublish the chapter (see below). The later option means that the chapter will not appear to end-users while they browse your knowledge base, but articles within the chapter will still appear in search results.