Depending on what you're doing at night, if you go out to eat and then a stroll down beach road... I'm sure you'll see plenty of girls that you're interested in and more than likely if you get eye contact they'll come up to you anyway.
It's not that you need to rove all the soi's and bars. If you can get 1/2 way down bangla without seeing a girl that you'd like to spend time with then you are not interested or hell of a picky guy.
Plenty around and very easy to grab. Great fun too
