Note file icons don't always show up

Phone: LG Optimus Fuel: LGL34C ;  Android 4.4 ; Logos Bible 5.1.1

NASB95 selected as preferred Bible which is downloaded into the phone.

I have separate note files for many books of the Bible (i.e. Hebrews, John, Amos etc.) . When I look at Hebrews in the NASB95 I can see all my note icons embedded in the text as I would see them on my laptop.

When I go any other book of the Bible in my phone I do not see any note icons.

When I go to Documents I can see the note files, open them, and verify that a note link takes me to the right location in the NAS95 Bible. But no note icon.

How do I get the note icons to appear? Perhaps I set something that I can't find. I don't know what to do. Thanks.

Update: This problem shows up persistently with the book of Amos (no note icons) so I tested it with the Gospel of John and at first didn't see the icons, but they showed up while I was typing this. However I've tried for a long time to get the note icons for Amos to appear and no matter how long I wait or try various settings, I don't see them.