Book Reports / Afghan cultural/social values cause characters to suffer "A Thousand Splendid" thesis [2]

My thesis for my research paper on a Thousand Splendid Suns is Afghan cultural and social values cause characters to suffer in Khaled Hosseini's A Thousand Splendid Suns. My teacher said that it is a fact and not a thesis . So I was wondering how I could make it argumentative and debatable and not a fact.