In my test, I created a simple query of Articles by Article translation title and section. The article that I placed in a subsection (a section within a section) does not display in the list. If I look at the filter list for Article translation title I can find it, but if I check the box next to the title of the article and click Apply, I get the message "No data available. Check your filters and calculations."

Further testing showed that if I started over again and added the metric D_COUNT(Articles), then the filter Article translation title, filtered by the title of the document in the subsection, it DOES show. 

At that point, I add Article translation title and section to the rows, and I can see the subsection article and the name of the subsection it's in.

Then I remove the filter for the Article translation title and I can see all of the articles and their sections.

Why do I have to first filter for just the subsection article(s) and then remove the filter to see everything?