When they find a remote tribe in the jungle why is it called a "lost tribe&

Question: When they find a remote tribe in the jungle why is it called a "lost tribe", when it was just!?

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Best Answer - Chosen by Asker:

Fuzzy use of language!. I don't know how anybody "goes missing," or "went missing," either!. Nor do I know why they keep calling Hidden Valley hidden now that there are freeway direction signs pointing to it!.!.!.Www@QuestionHome@Com