There may be an easier way, but I think this works:
SELECT `name`, SUM(sm) AS total FROM ((SELECT `name`, kns AS sm FROM tab1) UNION ALL (SELECT `name`, kng AS sm FROM tab2)) AS tbl GROUP BY tbl.name
You may benefit from using an user_id in order to relate your tables properly.
thank you very much, i really appreciate your answer
This is a very simplified example, i just want to learn how to do that