If you have never shaved your beard and don't intend to, then there isn't much advice we can give. If you want a full beard, then just keep growing as you are. There is nothing you can do to make it grow thicker or faster. It may well fill in more as time passes, but there is nothing you can do to make that happen sooner. You have a stylish beard right now. Enjoy what you have and just keep your fingers crossed for more in future.