Men (ο ανθρωπο). Generic use of the article (men as a class).
Shall not find it (ου μη ευρησουσιν αυτον). Strong double negative ου μη with the future active indicative according to Aleph Q, but ευρωσιν (second aorist active subjunctive) according to A P (either construction regular). The idea here is found in Job 3:21; Jeremiah 8:3. "Such a death as they desire, a death which will end their sufferings, is impossible; physical death is no remedy for the βασανισμος of an evil conscience" (Swete).
They shall desire to die (επιθυμησουσιν αποθανειν). Future active of επιθυμεω, a climax to ζητησουσιν (they shall seek), to desire vehemently. Paul in Philippians 1:23 shows a preference for death if his work is done, in order to be with Christ, a very different feeling from what we have here.
Fleeth (φευγε). Vivid futuristic present active indicative of φευγω. Even death does not come to their relief.