Many things greater than these lie hidden, for we have seen but few of his works: This verse is probably going to work better if the lines are reversed, as in New English Bible, which reads “We have seen but a small part of his works, and there remain many mysteries greater still.” We could also say:

• We know [or, have seen] only a small part of the Lord’s creation [or, the things that the Lord has created];
many things greater than these are still unknown.

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.