Complex sentence: To date, she has written 27 novels, all of which have been on the "New York Times" bestsellers list and have sold over 400 million copies and which have been translated into 40 languages.
Split into simpler sentences: To date, she has written 27 novels, all of which have appeared on the "New York Times" bestsellers list. In total, her books have sold over 400 million copies and have been translated into 40 languages.