The Lenovo video literally shows you a working device from the floor of CES. By how it works do you mean instead... (a) where the excess is stored, (b) how it's rolled, (c) what the (surely quite valuable) IP is?
That IP will be protected by patents, it won't survive by secrecy the first ifixit teardown or one of the bill of materials calculation sites will remove that veil.
https://patentscope.wipo.int/search/en/detail.jsf?docId=US43...
Like for example the Samsung Galaxy Fold Z phones.
https://www.samsung.com/en/smartphones/galaxy-z-fold6/
I wonder if they use the same kind of folding/rolling screen or not in that laptop they show in the OP article.
When I last looked at these kinds of phones in the store I found the screens super underwhelming. Maybe it has improved since.