Definitions
musungo: snare
riva: trap with a falling flat stone, for catching small animals
Translation
One (an animal) that cries is the one caught in a snare; the one caught under a stone trap believes the sky has fallen.
Inspiration
An animal caught in a snare could try and free itself, but one caught under a stone trap is completely incapacitated.
Application
People who complain about difficulties have most likely not experienced the worst. Those who have borne the brunt are silent, having resigned themselves to their fate.