Pages is a word processing app, not a database. When you search in it you are looking for words and phrases, not a page that they are on. Like most word processing apps the search feature is primarily for editing; finding and replacing text.
Besides, from what you are saying I think it is the final product, the book, that you want to be able to do the searches in. Pages is for creating. For searching the book you want to look at what format and reader you will export too. It does not matter too much what you use to write the book with, as long as it exports to the format you need; so it's that format you need to pin down before you decide what app to use when writing the book.
That said, I can't think of any ebook reader that does searches the way you want. Again, books are not databases; when you search in them you find words and phrases, not pages or records.
What you need to do what you want is an app, either special made for recipes or a general database.