As I understand it, parallel traders are people who travel to another country to buy genuine branded goods and then take them back to their own country to sell, but without the permission of the owner of the brand. These parallel traders have neither an export licence nor an import licence but they are travelling (usually across just one border, I think) to stock up on popular items which are cheaper in that other country, then transport them back to their own country to sell at a price which is lower than the public could normally find there, but which still makes the trader a nice profit.
In answer to your other question, not only is it acceptable to post from other reading material here, it is absolutely ideal when we are being asked to comment on the meaning or construction of something. Context is very important so the format of your post was pretty much perfect - meaningful title, context and a full question. Thank you!
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