I know that I can insert a second Table of Contents within the same document.

However, I saw in one document that the second Table of Contents only showed
the headings of that section. So in the first section I can see the complete
Table of Contents e.g.

1.
1.1
2.
2.1
3.
3.1 etc.

In the second section I only see

2.
2.1
2.1.1
2.2
2.2.1
etc.

Is there a special trick how to achieve this? My suspicion is that the
author has deleted all other parts of the second Table of Contents except
2.1..., however, it is very annoying every time I update the table as I get
the whole list again.

Any ideas?

Regards

Nicole