a few / few
I have a few books on my shelf at home.
(I have one or two books on my shelf)
I have few books on my shelf at home.
(I have a small amount of books on my shelf)
"I have many friends; I’ve known a few of them since primary school."
(a couple of them I've known for a long time)
"I have many friends; I’ve known few of them since primary school."
(not many of