Johan Andersen Thoen Moe, Holand, Akershus, Norway

I am trying to locate when Johan Andersen (thoen ) and wife Amave Christensdatter (Pauline Amelia Christensdttr Nygaard) and 2 sons, Jakob Marcus Johnsen Thoen and Anders (Andrew) Johnsen Thoen Came to America and on what ship. We know it was about 1870 as the next child was born in Minnesota, USA - 20 Dec 1870 Any and all help will be appreciated