Complex sentence: The bulk of the business continues to be derived from mail order catalog sales; however, with the re-launch of their website in May 2008, the Indiana Botanic Gardens has been focusing on expanding their online operations.
Split into simpler sentences: The bulk of the business continues to be derived from mail order catalog sales. With the re-launch of a their website in May 2008, the Indiana Botanic Gardens has been focusing on expanding their online operations.