The print edition doesn't include Chapter 7 ("Searching") from the web edition. (There may be parts of the other chapters missing, but I'm not sure.)
That said, Chapter 7 of the web edition begins this way:
> This chapter does not introduce any new JavaScript-specific concepts. Instead, we will go through the solution to two problems, discussing some interesting algorithms and techniques along the way. If this does not sound interesting to you, it is safe to skip to the next chapter.
So maybe the author or the publisher (or both?) decided that chapter was a distraction or somehow wrong for the printed version.
