It depends on where you think your gaps are, but some of the soft skills of communication are discussed in these books that I've learned a bit from each: It's Not All About Me by Robin Dreeke an FBI Social Engineering expert, How to Win Friends and Influence People by Dale Carnegie, Crucial Conversations by Patterson et. al. Not to say you should change your techniques to be "convincing" or salesman-like, which some of these books seem like, but you may learn some of what you do today that can be altered to help with communication.

I was going through a HN "best books" thread recently and found someone recommending "How to Speak How to Listen" by Mortimer J. Adler. I'm about halfway in and there are loads of great tips in it!