In Danang, surprisingly, the best place to talks to gals is along the promenade alongside the river at Bach Dang.
Go around 5pm (it gets dark quite early in central) when everyone has finished work etc and going for their evening walks.
I was walking alone with a camera (tell tale sign of a tourist) and several gals smiled at me, they are usually very friendly towards foreigners. I saw a young lady walking her dog and asked the name of her dog (she had trouble understanding me as my accent is northern). Then she asked me in English where I was from....
I even saw one ang moh chatting up 2 ladies.