Eccl 1:2

1:2 Vanity. The Hebrew word means “breath” or “vapor,” and hence what is “insubstantial,” “useless,” or “futile.” Human death makes the deeds and desires of people who build earthly culture (“under the sun”) useless.

All. This word is qualified by the phrase “under the sun” (v. 3) and means everything people experience with their senses (v. 8).