Why aren't Sourcebooks searchable?

I am running Princes of the Apocalypse and for a story reason I wanted to see if the book had any mention of The Stone Bridge, and so I opened the book prepared to search for "The Stone Bridge" to see if the phrase showed up anywhere and imagine my surprise to learn that the books are not searchable. 

What's the justification for not including such an obviously useful tool?

Google:

"the stone bridge" site:dndbeyond.com

I'm talking about searching within a specific book.  It's just baffling to me that such a simple tool does not exist.  If I open a PDF I can search for a word or phrase, but not in D&D Beyond book?

Open the book in D&D Beyond, CTRL - F.

Valid point, but I doubt we are getting any QOL new features in D&D Beyond for a while so I was just offering an alternative approach to using the awful search tools within D&D Beyond. It's not ideal but it is fairly quick.

Quote from faze4guru >>

I'm talking about searching within a specific book.  It's just baffling to me that such a simple tool does not exist.  If I open a PDF I can search for a word or phrase, but not in D&D Beyond book?

Ahh, I get it. Yes, I 100% agree with you.

Especially now that legacy items do not appear in lists like Spells, I am finding that I have to search the 2014 PHB for content.