[color=red]1-The people you don’t know well, you do not talk to them about these matters.
meaning:
[color=indigo]You do not talk to the people you don’t know well about these matters.
[color=red]2-People you don’t know well, you do not talk to them about these matters.
meaning:
[color=indigo]You do not talk to people you don’t know well about these matters.
For me, the second is more natural, but I would hardly notice if someone said the first instead. Though OK in spoken English, in written English this sentence structure looks unpolished.