The works of all flesh are before him, and nothing can be hid from his eyes: The meaning here is well expressed in Good News Translation. Compare 17.19. Contemporary English Version is also helpful:

• We can’t hide from God;
he has watched everything
that each human has done.

Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on Sirach. (UBS Helps for Translators). New York: UBS, 2008. For this and other handbooks for translators see here.