macOS AppleScript: Can't get content from scroll view

[gwarth]

Hi everybody,

I'm new to AppleScript and after facing and solving a few things I'm pretty stuck now. I simply won't get the content out of a scroll view.

if the name of theObject is equal to "btnCreateQpassArchive" then
	set yadda to text view "txtShortDescription" of window "main"
	display dialog yadda
[...]

The error will be: Can't get class texV "txtShortDescription" of window "main".

Now, I've read somewhere it needs to be (which doesn't work either):

[...] text view of scroll view "txtShortDescription"

But... how do I know stuff like this in case this was working? Where's the reference stuff for all this?

Thanks so much!
Georg

[edit]
Forgot to add a screenshot...

[/edit]