Writing all zeros in latch
You can just ground (0V is usually take as a zero) each of the latch input bits.

I suppose you really mean that you'd like to optionally latch zeros, though. (It is hard to imagine you'd just want to only latch zeros.) In that case, just preceded the latch with a mux and ground one of the mux inputs, selecting that one when you want it. Or, some latches may include a clear input, as well, either synchronous and asynchronous. So that may be another option, as well.

I've already written probably twice what you did in writing your question. You really should get in the practice of writing more, so that people writing answers can write less.