Your comments aren't constructive either. Instead of asking the issue, you instantly think that the guy is talking nonsense.
The issue is in the Nguyễn Khoa Đăng - Đồng Văn Cống intersection and Đường số 80 - Đồng Văn Cống intersection. There are ways that don't connects to each other, or nodes that overlaps and a way hidden behind others.