Polish uses plural, but it doesn't specify whether it's 'these apples' or 'these apples, oranges and bananas'. As for English, it was always difficult for me to figure out how to use 'fruit' as a mass noun. I think the version here is correct and can mean both singular fruit and plural, and as for yours... I think that's okay as well, although I'm not sure.
English native here: "Fruit" is almost always treated as an uncountable noun, so "this fruit" does correspond best to the Polish "te owoce." For just a singular fruit, we generally say "a piece of fruit." The plural form "fruits" is used only in special circumstances, for instance, sometimes when you are talking about different kinds of fruit — "My favorite fruits are apples and bananas."
"Do these fruits come from Poland" is perfectly valid and should be accepted—it would imply (to me, at least) that you are talking about the different kinds of fruit that come from Poland. "Does this fruit come from Poland" is a little more common and conveys a broader spectrum of possible usages.
"Te owoce" = "this fruit" will always be a good translation (whether there is one kind of fruit or many).
I am from the US. I think the usage of fruit/fruits is pretty much the same in all English dialects (at least, I have never heard it used differently in other countries).
The top two or three answers here are very helpful.
"Fruit" can refer to, for example, one apple, two apples or twenty apples, but it is not gramatically a matter of being singular and plural, but of being uncountable, which means it always takes a singular verb.
I think we'd normally also use a singular demonstrative ("this"), but that we perhaps have a weird exception here, and that it could also be possible to say "these fruit", when looking at several different types of fruit, for example "Can you name these fruit?" So it's possibly a case of "can say", but not, I think, of "should say".
I don't think it's a prefix here - not in this meaning of "pochodzić".
But you can also add "po-" to many verbs and it has a meaning like "to do something for some time", "to spend some time doing something". In this way "pochodzić" can mean "to walk for a bit". Kinda like in "I want to stretch my legs" ;)