As they search for evidence they can use to impeach President Biden, House Republicans have repeatedly pointed to evidence that they say undercuts his claims that he never had anything to do with the foreign business dealings of his son, Hunter Biden.

As vice president, for example, Mr. Biden did briefly meet with some of his son’s business associates, though there is no testimony that he had any substantive discussions with them or that he changed government policy to benefit any of Hunter Biden’s ventures.

Still, Republicans have continued to mine voluminous records related to Hunter Biden, including a trove of messages from a computer hard drive, to try to make a case that Hunter Biden’s income from abroad was at the heart of an influence-peddling operation that enriched the entire Biden family, including his father.

Republicans have used quotes culled from text messages or emails to add a confessional quality to their presentations — evidence, they say, that Hunter Biden was essentially admitting that he and his father were engaged in political corruption.