JOHNSEN brothers from BERGEN

Hi... I am trying to find anything more abouth these relathives Oluf Andreas Johnsen b may 1858. He left the ship " Flora " in NY nov 1878 Karl Johnsen b 28 jun 1865. I don`t know when he left Bergen Nicolay Aug Johnsen b 15 jul 1865 He left the ship " Gustav Adolph" in NY in may 1883 Marius Johnsen b 5 oct 1868. He left Bergen aug/ sept 1894 Anyone who can help me here ??