I'm SO confused about the shipping policies here!! (São Paulo)

First of all, I want to just say that I am simply looking for some vitamins/supplements/herbs that would be very easily found at every GNC or a wholefoods in the US, and at many grocery stores. So if anybody has any leads on that end, I'd be grateful. Every single supplement store i've seen is basically just items for sports or bodybuilding, and even the specialty stores like mundo verde does not carry a fraction of things basically found in the US.

So the shipping. I was told i could order off amazon.com, as long as it's under 50 dollars worth. But then someone said that it will be stopped if it is sent directly from the seller. So my other choice is to have family or friends send me items, that are worth under 50 dollars, BUT that shipping to me would cost a ridiculous arm an a leg? I'm so baffled by these policies i've heard of thus far