Qu\u1ea3ng Tr\u1ecb: G\u1ea7n 300 h\u1ecdc sinh \u0111\u01b0\u1ee3c x\u00e9t nghi\u1ec7m SARS-CoV-2 tr\u01b0\u1edbc k\u1ef3 thi<\/a><\/blockquote><\/iframe>