by Little, Brown, $7.95. “Her Life. Her Secrets” is the subtitle, fair warning that the author’s approach is sob-sisterish and his facts derived largely from Chanel, who was inventive with them. But Mr. Haedrich is not as naive as he pretends, and this biography achieves considerable interest despite its exasperating percentage of chichi. Illustrations. Translated by Charles Lam Markmann..