“Story not generally known” in Japanese
Short answer
Story not generally known in Japanese is “裏話” (urabanashi). Full meaning: inside story, the real story (behind something), story not generally known.
Other ways to say “Story not generally known” in Japanese
裏話し
urabanashi inside story, the real story (behind something), story not generally known
ウラ話
urabanashi inside story, the real story (behind something), story not generally known
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