So, from what I've read, and this is only in the U.S.,
Country of origin marking for goods is required for each thing of a foreign origin. So if I'm a company and I'm assembling a car for example, if the tires came from Mexico, the windows from Taiwan, and the chassis from Germany, then each one of those things needs to be properly labelled with their countries of origin.
Made in the U.S.A. is a type of country of origin label with strict requirements. I think all or nearly all of the product is made in the U.S.
This schema is similar among most countries, I think.
Anyway, this has more to do with international trade laws and such than it does with actual English, so don't worry too much about getting it right?