Has anyone else noticed that iBooks search does not find all information that should be located for a specific search criteria?

Question

I am converting a novel to ePub format.  I am currently in the process of adding "end notes" to the book.  Each will have a flag embedded at the proper spot in the various chapters that is coded as "[See End Note xx]" where xx is a one or two digit number.  Each of the flags has those words surrounded by the HTML that links the flag to the proper end note at the back of the book.
To verify that I have indeed inserted correctly each end note, I copy the book's epub file from my desktop PC to the iPad.  I then do a search in iBooks to locate each occurance of "[See End Note" or just "End Note".  I should see each of these flags listed.  Last night it would list all of them except "[See End Note 28]"!   If I did a search for "28", it would appear.
I then copied just the flag itself ("[See End Note 28]") without the associated linkage HTML to the back of the document, and placed the copy just in front of the paragraph that contains it. Neither of the two flags were found.
I then duplicated just the flags for end notes 27 and 29 which the search function had located.  I placed the copies surrounding the copied flag for 29.  The result was as follows in the text of the book:
[See End Note 27]
[See End Note 28]
[See End Note 29]
Although 27 and 29 were still being shown in their normal places, none of the above three inserted (test) flags was displayed by the search!
It seemed that the iBooks search goes through part of the book, but cannot take the whole book in one piece.  It then continues, but leaves a gap that is not scanned per the search criteria.  To test that theory, I removed the entire text of several chapters that did not contain any end notes.  I then loaded this modified copy of the book into the iPad.  When I ran a search using "End Note", all of the flags (including the special test flags) were displayed.  The list included the "missing" "[See End Note 28]" that cannot be found if the all of the chapters have their text!
I shall be calling Apple in a few minutes to again attempt to get the apparent "bug" (aka design or coding flaw) removed such that it does not
impact the ability of the iPad to be a useful tool.

Answer 1

Not all movie studio signed up to the agreement with Apple to allow redownloading of movies, only those that did will have their movies available in the purchased section of iTunes.