This is typical Doppler. There is a slow introduction in a minor key with florid writing for the soprano and the flutes, followed by a major Allegretto section. All the tunes are based on Hungarian folk music. The writing is not as difficult as is generally found in these types of pieces because although there is some dovetailing between the players, the vocal part looks exactly like a flute part. In fact this would probably work very well with three flutes and piano.
From the Publisher
Difficulty level, roughly compared to ABRSM exam grades. 0 is beginner, 9 is advanced (beyond grade 8).