Unfortunately theme design is restricted to the core element limitations. Basically you can add a sidebar to either the left, or right, but not both. The content section is comprised of a left place section, and a right place section. These elements are not created by the theme. They are called from the core to display. They get their functionality from the core. Theme designers can only change the visual appearance. The left place section is the area to the left of the newsfeed, and the right place section is where the newsfeed will display. The sidebar will be located on the left, or right, and the core will automatically populate the sidebar with the user profile link at the top, and the add new widget, and finally a top section, and bottom section. These make up the content section.
You might try discussing with one of the commercial theme devs in the store to see if there is some optional possibility with a custom theme. The closest one is here, but it is only on the index page, and looks like the just resized the sections.
https://developers.oxwall.com/store/item/997