There are a couple of unofficial study guides for VCAP-DCV - mostly for old versions (5.5 or 6.0), but they are still great for preparation.
VCAP6.5-DCV Design Prep-Guide - vBuffer
https://vbrownbag.com/category/vmware/vmwarevcap/
Unofficial VCAP6-DCV Design Study Guide - vCallaway
They helped me to pass the exam in this summer 