Horejsi

I am looking for the family of my great grandfather, Franz Joseph Horejsi, born 21 Jul 1891, in Slavnovice, South Bohemia, Czech Republic. We know very little about them. His fa is prob Franz J. Horejsi and his mo is prob Mary Plovah. He emigr in 1911 on the SS Kronprinz Wilhelm. We have been very curious about his family and why he immigrated for decades. Any help will be gratefully appreciated. As we look forward to knowing our lost relatives. Thank You, Michelle Doege.