Snatch, noun: a brief, fragmentary, or hurried part.

Source: https://www.merriam-webster.com/dictionary/snatch

We encountered the plural form of this word in the second chapter of Quicksand. It is used to describe the activity that Helga hears outside her door while she hides in her room.

“In the corridor beyond her door was a medley of noises
incident to the rising and preparing for the day at the same
hour of many schoolgirls—foolish giggling, indistinguishable
snatches of merry conversation, distant gurgle of running water,
patter of slippered feet, low-pitched singing, good-natured
admonitions to hurry, slamming of doors, clatter of various
unnamable articles, and—suddenly—calamitous silence.”