Try it

SELECT * FROM gallery2 WHERE topic_id="1527559" UNION SELECT * FROM gallery2 WHERE topic_id="198810" UNION SELECT * FROM gallery2 WHERE topic_id="1222578" UNION SELECT * FROM gallery2 WHERE topic_id="444286" UNION SELECT * FROM gallery2 WHERE topic_id="1806303" UNION SELECT * FROM gallery2 WHERE topic_id="542536" UNION SELECT * FROM gallery2 WHERE topic_id="1105262" UNION SELECT * FROM gallery2 WHERE topic_id="756397" UNION SELECT * FROM gallery2 WHERE topic_id="1555314" UNION SELECT * FROM gallery2 WHERE topic_id="1322314" UNION SELECT * FROM gallery2 WHERE topic_id="206865" UNION SELECT * FROM gallery2 WHERE topic_id="428662" UNION SELECT * FROM gallery2 WHERE topic_id="1742808" UNION SELECT * FROM gallery2 WHERE topic_id="154914" UNION SELECT * FROM gallery2 WHERE topic_id="1187037" UNION SELECT * FROM gallery2 WHERE topic_id="215813"