What I found is that written evidence for knocking on wood (and for the history of gesture as a whole) is remarkably sparse. In the Penguin Guide to Superstitions, folklorist Steve Roud offers a skeptical take on the provenance of knocking on wood due to the near total absence of written records about it:
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。同城约会对此有专业解读
ВСУ запустили «Фламинго» вглубь России. В Москве заявили, что это британские ракеты с украинскими шильдиками16:45
最后，通过开源走向全球，如今，其海外收入已经超越国内市场。
有客人钻进包厢了，几只反应迅速的“老虎”立刻拎着化妆包在包厢外排起了队，等待被客人选中，落选的小姐只能回到座位上等着下一次机会。