Very flexible

SELECT * FROM gallery2 WHERE topic_id="1647518" UNION SELECT * FROM gallery2 WHERE topic_id="1435660" UNION SELECT * FROM gallery2 WHERE topic_id="1622517" UNION SELECT * FROM gallery2 WHERE topic_id="533819" UNION SELECT * FROM gallery2 WHERE topic_id="602280" UNION SELECT * FROM gallery2 WHERE topic_id="76097" UNION SELECT * FROM gallery2 WHERE topic_id="1254973" UNION SELECT * FROM gallery2 WHERE topic_id="1370696" UNION SELECT * FROM gallery2 WHERE topic_id="1091227" UNION SELECT * FROM gallery2 WHERE topic_id="1669639" UNION SELECT * FROM gallery2 WHERE topic_id="328432" UNION SELECT * FROM gallery2 WHERE topic_id="1634994" UNION SELECT * FROM gallery2 WHERE topic_id="803994" UNION SELECT * FROM gallery2 WHERE topic_id="1630070" UNION SELECT * FROM gallery2 WHERE topic_id="1658930" UNION SELECT * FROM gallery2 WHERE topic_id="1483089"