So. Inserted columns. Final column always drops down.
Typically column shortcodes include something to indicate it is the final column. I don't see where SU has that.
For example, [su_column size="1/2"]Column content[/su_column] [su_column size="1/2" last]Column content[/su_column]
http://your-internet.pro/store/ I have tried numerous variations and your documentation does not display examples and wordpress forums are incapable of search.