Unlike western business relationship which remains professional and perhaps, a lot of, even after a long time, Chinese business relationship inevitably becomes a social relationship.
The more you share your personal life, including family, hobbies, political views, aspirations, the closer you are in your business relationship. Sometimes, a lot of time is spent in discussing matters outside of business, but then a lot of time, the other party is also making up his mind about your deal based on how much he sees your personal relationship with him.