Editing e-commerce website values
I think the code is a little dodgy, and the design is dodgy. I'd store the translation in a dictionary of some sort.

But addressing your immediate question, to simplify the code you have, you could do....

public void EditProduct(string element, string text1, string text2, bool edit1, bool edit2, string culture)
        {
            var product = DoSomeMagicToGetAProduct();

            var arText = culture == "ar" ? text1 : text2;
            var enText = culture == "en" ? text1 : text2;
            var updateEn = culture == "en" ? edit1 : edit2;
            var updateAr = culture == "ar" ? edit1 : edit2;

            if (element == "title")
            {
                if (updateEn) product.Title = enText;
                if (updateAr) product.TitleAr = arText;                    
            }

            if (element == "description")
            {
                if (updateEn) product.Description = enText;
                if (updateAr) product.DescriptionAr = arText;   
            }

            if (element == "excerpt")
            {
                if (updateEn) product.Excerpt = enText;
                if (updateAr) product.ExcerptAr = arText;   
            }

            product.Save();

        }