You need to send in 4 arguments to express your two conditions:
...?status=Åben;status-opt=%3d;fk_type_workorder=4;fk_type_workorder-opt=%41%3d
Don't let the "=" in "=4" fool you; it merely sets the value on the right-hand side of the SQL expression that ultimately results. The "-opt" sets the operator, which will be '!=' (escaped to %41%3d so as not to be considered part of the next token in the URL; I'm not positive this is necessary but it should work), or '=' (%3d), or any valid SQL comparison operator that you want.
...?status=Åben;status-opt=%3d;fk_type_workorder=4;fk_type_workorder-opt=%41%3d
Don't let the "=" in "=4" fool you; it merely sets the value on the right-hand side of the SQL expression that ultimately results. The "-opt" sets the operator, which will be '!=' (escaped to %41%3d so as not to be considered part of the next token in the URL; I'm not positive this is necessary but it should work), or '=' (%3d), or any valid SQL comparison operator that you want.