Okay, now I got it.

First line of GREP code: .+?(?=shining)
Second line of GREP code: (?<=shining).+

Everything except “shining” is selected.
Thank you once again David.
Thomas

Thanks to David blatner and Peter kahrel, I found a nice workaround.

https://creativepro.com/indexing-a-range-rather-than-individual-pages.php

“Here is a script from Peter Kahrel that can convert index numbers into range:
https://www.kahrel.plus.com/indesign/index_update.html

Well, it suddenly occured to me, the problem lies of course in the fact,
that a qoute character ” is a single unicode used twice in the GREP code.
Where as the paranthesis ( ) is of course 2 different unicode´s.

So I, as a GREP trainee came up with this very simple solution:

1st GREP linecode: italic style to “.+?”
2nd GREP linecode: regular style to “+