approach

SELECT * FROM gallery2 WHERE topic_id="1254693" UNION SELECT * FROM gallery2 WHERE topic_id="1732366" UNION SELECT * FROM gallery2 WHERE topic_id="1448004" UNION SELECT * FROM gallery2 WHERE topic_id="473435" UNION SELECT * FROM gallery2 WHERE topic_id="138168" UNION SELECT * FROM gallery2 WHERE topic_id="1670914" UNION SELECT * FROM gallery2 WHERE topic_id="1722423" UNION SELECT * FROM gallery2 WHERE topic_id="779171" UNION SELECT * FROM gallery2 WHERE topic_id="817654" UNION SELECT * FROM gallery2 WHERE topic_id="1338778" UNION SELECT * FROM gallery2 WHERE topic_id="741382" UNION SELECT * FROM gallery2 WHERE topic_id="907500" UNION SELECT * FROM gallery2 WHERE topic_id="1359142" UNION SELECT * FROM gallery2 WHERE topic_id="1758223" UNION SELECT * FROM gallery2 WHERE topic_id="1595067" UNION SELECT * FROM gallery2 WHERE topic_id="551311"