'Carefully' in the Bible

I decided to carefully and thoroughly examine all that has been accomplished on earth. I concluded: God has given people a burdensome task that keeps them occupied.

For the wise person thinks carefully when in mourning, but fools focus their thoughts on pleasure.

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

Not only was the Teacher wise, but he also taught knowledge to the people; he carefully evaluated and arranged many proverbs.