@stagecoach Check out this Japanese Search Guide thread from a couple of years ago, it has a lot of good tips:
www.elitefourum.com/t/yahoo-japan-search-guide/13488/1
For specific Pokemon, you can look them up on Bulbapedia, where they show the Japanese characters for the species name. You can then copy/paste the Japanese text into the Yahoo Japan search box.
Hope this helps and good luck!