Honestly, there are experts available on crowd-sourced flight search enginers like Flightfox.com (see my profile for a discount link).
On there, you can say, ask for a flight from Central Europe to Thailand/Cambodia etc (there was a flight last week on there from San Francisco to "anywhere"!), and all the dates criteria you like, and have people search for you.
Yes it costs, but if they can't beat your price, you get your money back. And so far, for me, they've always saved me money.
(Disclaimer: I'm not affiliated, but I do compete on there to find the best prices, and have met the founders)