Rugland

I am looking for my great great grandparents. Thore Thorson Rugland and Johanne Sannon. I know Thore came here in 1912 But after that I can not find him. Him and two sons went to Chicago, Il. Now Johanne stayed in Norway. I would like to find her family. On her son death cert. it gives her maiden name as Sannon. In the 1900 cen. it gives it as Rugland. When her daughter Naima Rugland came over it gives the name Johanne Foss. Can anyone help?? Thank you very much!!