Ecclesiastes 6 bemoans the situation where a person works for another and does not reap the benefits of his or her work. It is unfulfilling to work hard and then not see the reward.
Ecclesiastes 7 is a collection of proverbs many of which I do not understand. Solomon is clearly struggling with the choices he has made and is in a depression of sorts. Even though he was given wisdom he did not always use it in making decisions for his own life. Now he is living with the consequences.
Psalms 95 and 96 are both praise psalms, extolling the greatness of our God. Psalm 95, though, seems to be missing an ending.