In literature database searching, we show that it is necessary to use plural databases for a more improved search. We also compare the results of a single database search with that of multiple database search in the domain of Japanese life sciences. We searched the MEDLINE and EMBASE using the same search terms. There were some differences in the results, owing to differences in the journals and recording methods. We herein show some of the differences in the journals contained in both databases. Furthermore, we show the differences in the number of papers derived from the same journal. Next, as an example of a practical search, we selected some universities in Japan, searched both databases regarding papers published from these universities and then merged the results by hand. According to our results, only 63% of all papers were common to both databases.