Here are the two replies from the Answers section:

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'Some' is completely neutral. It gives no indication of quantity.'Some apples' is the opposite of 'no apples'.

'A few' means also 'some', but it is not neutral, as it indicates that there are not many apples.

NB Remember that there is a difference between 'a few apples' and 'few apples'.

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A few is an unspecified small number. Some is an unspecified number that may be big or small. From what you wrote there isn't enough information decide which is bigger in this case.

I'm not 100% sure but hope someone will correct me if I'm mistaken. I think you can't use "a few" with uncountable nouns like milk, water and so on; some = a few for countable nouns.