SQL & PL/SQL

Hello gurus,

I have table a containing around 7 milion records and trying to retrieve z record.
I have tried to this script

SELECT id, name
FROM
(
SELECT ROWNUM rn, id, name
FROM table_a
ORDER BY name
)
WHERE rn BETWEEN 5 to 10;

Already use index for the table and it retrieve fast if I start from rownum = 1.
And have tried using hints FIRST_ROWS but doesnt do any good.
Is there any way to make it faster?

Thank you so much
henry