'Observed' in the Bible

I observed every activity done on earth. My conclusion: all of it is pointless like chasing after the wind.

The only worthwhile thing for a human being is to eat, drink, and enjoy life's goodness that he finds in what he accomplishes. This, I observed, is also from the hand of God himself,

I have observed the burdens placed by God on human beings in order to perfect them.

I observed everyone who lives and walks on earth, along with the youth who will take the king's place.

I have observed a painful tragedy on earth: Wealth hoarded by its owner harms him,

Look! I observed that it is good and prudent to eat, drink, and enjoy all that is good of a person's work that he does on earth during the limited days of his life, which God gives him, for this is his allotment.

There exists another misfortune that I have observed on earth, and it is a heavy burden upon human beings:

I observed all this, and carefully considered everything that is undertaken on earth, especially the time when someone dominates another to his detriment.

I considered and observed on earth the following: The race doesn't go to the swift, nor the battle to the strong, nor food to the wise, nor wealth to the smart, nor recognition to the skilled. Instead, timing and circumstances meet them all.

I also observed this example of wisdom on earth, and it seemed important to me:

Here's another tragedy that I've observed on earth, a kind of error that comes from an overseer:

And I have observed servants riding on horses, while princes walk on the ground like servants.