Luciano
What documentation do YOU have on your ancestor? You need to backtrack from yourself going backwards to find information. The church records are indexed by a village and then religion, not by a surname. The surname you are using could very well have been slightly different in Poland. SKI ending to me does not suggests Lemko. Was your ancestor Byzantine Catholic? BENDASZ might be Lemko/Ruthenian name but SKI does changes it to Polish.
In Slovak, the ending SKY means that the surname originates from a village by that name but not that you would actually find a surname in that village now.
Do you know Polish?
www.moikrewni.pl/mapa/_nameswww.herby.com.plhttp://baza.archiwa.gov.pl/sezam/pradziad.php?l=en