First a translation of what you are about to hear.
Polish > English
Oh you river, you river
Why are you not full?
Oh, luli luli luli...
Why are you not full?
Oh, how could I be full?
People come to drink water
Oh, luli luli luli...
People come to drink water
People come to drink water
Jasieńko comes to water his horse
Oh, luli luli luli...
Jasieńko comes to water his horse
Jasieńko comes to water his horse
Kasieńka comes to extinguish the fire
Oh, luli luli luli...
Kasieńka comes to extinguish the fire
Laboratorium Pieśni (Song Laboratory) - ty rzeko (Oh you, river)