Eclesiasts 9:10 vs Samuel 2:6

Prediger 9:10 
"... for in the realm of the dead, where you are going,
there is neither working nor planning nor knowledge nor wisdom."

The Sheol (realm of the dead ) was by the Jews a kind of jail-hell,
where one has to suffer for the bad deeds of one's previous life;
Thus there were no posibility to work, plan, aquire knowledge or wisdom in hell...
and what happened afterwards?

The thoghts of of the jews in this conection are recorded in
1.Samuel 2:6 "Jehova The Lord brings death and makes alive; he brings down to the grave and raises one up (again)."

So this is a way to describe reincarnation, than after one dies , one will be reborn again and becomes alive.
This was the thought of the ancient world at that time, concerning the rebirth.

1. the Hebrews did not claim that the rebirth should happen sometime in the distant future (as the christians invented).
2. they did not link the rebirth to the belief in a "Son of God".
3. they did not bind the rebirth with an "eternal damnation",

as it was invented later in Christianity, see Eternal Damnation.