sql查询在没有UNION的情况下执行多个条件

Question

我是mysql的新手。所以基本上我用以下两个条件执行搜索

(SELECT * FROM `mytable1` WHERE MATCH(`title`) AGAINST ('cars'  IN BOOLEAN MODE) AND `domain` = 'one' ORDER BY `seed` DESC LIMIT 5)
union all 
(SELECT * FROM `mytable1` WHERE MATCH(`title`) AGAINST ('cars' IN BOOLEAN MODE) AND `domain` = 'two' ORDER BY `seed` DESC LIMIT 5)

但是这个查询太慢了，我的网站在高流量后崩溃了。是否有可能重写上面的查询以获得更好的性能？

谢谢。