In English, "few" means a small number, and "some" means a number that is any size, probably not the highest percentage, but unknown. In Spanish, "few" and "some" can be interchangeable in some situations. It may be the same in Italian because both Spanish and Italian are dialects of Latin. Can anyone whose native tongue is Italian confirm my hypothesis?
TheGandalf, your example did not differentiate sufficiently.
Both "Few have food" and "A few have food" can mean "The number of people who have food is small." "Few" is an indefinite English pronoun, which means that the number is uncountable.
"A few have food" can also mean there is a definite number of people who have food, but the percentage of that number is both small and unknown. The English indefinite pronoun "a" is what indicates that the percentages is discoverable if one takes the trouble to count how many people/animals do have food.