Thirty spokes meet at a hollowed-out hub;
the wheel won't work without its hole.
A vessel is moulded from solid clay;
its inner emptiness makes it useful.
To make a room, you have to cut doors and windows;
without openings, a place isn't livable.
To make use of what is here,
you must make use of what is not.
Most of the various translations are very similar, especially in the first half dozen lines. There are some variations in the last two.
Gain can be had from somethingness,
But use can be had from nothingness. (Herrymon Maurer)
Therefore, we regard having something as beneficial
But having nothing as useful. (Robert Henricks)