כִּ֠י מֶֽה־הֹוֶ֤ה לָֽאָדָם֙ בְּכָל־עֲמָל֔וֹ וּבְרַעְי֖וֹן לִבּ֑וֹ שֶׁה֥וּא עָמֵ֖ל תַּ֥חַת הַשָּֽׁמֶשׁ׃
For what hath a man of all his labour, and of the striving of his heart, wherein he laboureth under the sun?
Read kabbalistic (mystical) interpretation of Ecclesiastes 2:22: and classical mystical sources.