'Efforts' in the Bible

What does a man gain for all his effortsthat he labors at under the sun?

Then I examined all of my accomplishments that I had brought about by my own efforts, including the work that I had labored so hard to complete and it was all pointless, like chasing after the wind, and there was nothing to be gained on earth.

So I turned aside and let my heart despair over all the fruit of my labor for which I had labored under the sun.

For what does a man get with all his work and all his efforts that he labors at under the sun?

It is also the gift of God whenever anyone eats, drinks, and enjoys all his efforts.

Two are better than one because they have a good reward for their efforts.

As he came from his mother’s womb, so he will go again, naked as he came; he will take nothing for his efforts that he can carry in his hands.

then I discerned all that God has done: No one really comprehends what happens on earth. Despite all human efforts to discover it, no one can ever grasp it. Even if a wise person claimed that he understood, he would not really comprehend it.