How to make a selection by article tags in Google Analytics?

Question

Google

There is a news site. All articles have tags (the site is medical, respectively, linking to sections of medicine). You need to make a selection like: "Obstetrics most viewed articles."
Logically you have to do

...
ga('set', 'contentGroup#', 'Акушерство');
ga('send', 'pageview', 'auto');

But the question is, my articles can belong to several content groups at once and it is necessary to calculate for both. How to do it right? But I do not need to send pageview
several times because the page itself is still viewed 1 time.