Hi Oleg, Marie,
Thank you for your answer. I thought too that some algorithm as changed and has been applied in the same time with Emanuel update.
Oleg, I read about Emanuel penalties poor quality content. I am sure that I have a very good quality content but my appreciation it can be not same with google. I write the content using over then 3 sources and is unique. I thought that Emanuel penalties me for the pour quality content.
Marie, the rankings were the same for over 3 months . Maybe they has some link building strategy The domain is old. The position was ranked by SeoMoz ranking and me with incognito search.
Do you think I should go on with link building strategy?