Am thinking of staying 14 days in Poland in springtime of next year. My main purpose is a fact-finding mission
In my opinion I feel that is too short for an anthropological study. I also figure that you need someone close by with you that knows the place to show you around as you still need to learn the language, to tell you about good places to live, things to do, job/market etc. maybe bring along a relative or friend. I feel things are much more interesting if you have someone to tag along to share the experience with.
You should do it, it will be fun.