I created a view with 2 FILTER CRITERIA (Content: Has taxonomy term) exposed to visitors.
For testing purpose, I have 2 vocabularies with 2 terms inside :
I have 2 articles. Article 1 on only PART of T1.
If I select T1 and Any, I have no results but I should have result because I use OR operator(see screen shot).
If this article is T1 and T3 and i select T1 and T3, it works. If I select any and any, it works and i see my 2 articles.
See 2 cases :