Hi Aladdin1404 and welcome to our community
You are talking about two different things that appear to be
related, but probably aren't.
You said that "AAE" is in your Index and linked to a topic.
But you refer to search, which is a different animal. Search allows
trawling through all the output files and finding occurrences of a
specific term, while the Index may contain terms that really don't
even have to exist in topics. Perhaps AAE refers to the "Add
Another Entity" topic and is in the index only because users only
ever refer to it this way. In this case, AAE would never be found
using Search. Search also may not provide desired results. There
are lists that govern what is excluded and whatnot. And I believe
search uses a "stemming" mechanism. So some words may not even be
found if you type them completely.
On a personal note, I've always left Search alone, preferred
and stressed use of the Index as the primary way to find things in
help. I am aware that Google has changed the playing field for user
expectations with Search. While it's good for the web, it's
generally bad for help systems.
Cheers... Rick