Hi Michele,
unfortunately since PTC migrated the community to the new Lithium platform, many things have stopped working and even more documents, images and videos have become unattainable.
You can try to reach community admin to ask if the link could be restored (pick the three dot in the right upper corner and select Notify Moderator) or use this link https://community.ptc.com/t5/user/viewprofilepage/user-id/272431 and then send her a private message.
In any case, the construction of a sub-selection is quite complicated so I suggest you use, as an example, the one you find attached to this discussion https://community.ptc.com/t5/Windchill-Questions/query-builder-Latest-Revision/m-p/451237
If you haven't yet done, give a read also to this document, where there are some very useful notes for those who use the reporting tool https://community.ptc.com/t5/Windchill-Questions/Resource-for-reporting/td-p/448738
In the document you can also find links to dozens of ready-to-use reports, including some useful for building sub-selections.
Last but not least, if I have found your correct references, we work a few kilometres away, so instead of writing to us in English, you can also click on my profile in the community and write me directly in Italian so we can understand each other better.
Marco
