The House of Representatives voted Wednesday to block the Justice Department and the FBI from using the USA Patriot Act to obtain library records and bookstore sales slips. The vote reversed a narrow loss last year. It still would allow the government to continue to seek out records of Internet use at libraries. Thirty-eight Republicans joined with Democrats in the vote. President Bush has threatened to veto any bill that bars the government from going after library and bookstore records. Many librarians have defied the government by disposing of records quickly in an effort to protect people’s privacy.