Why can't I get a full text document that I found at PuntoQ?

The results that you find at PuntoQ are database contents based on your search. However, the ULL does not provide access to the full text of every document. For this reason, if the ULL have two articles that belong to the same magazine, one published in 2001 and the other published in 2010, and we can have access to the full text of the more recent one, we wont be able to access to the full text of the other article.This can occur because the ULL have only provided the full text access of articles from 2005 up to now.