On the Japanese-language pages, you can use Kanji, Hiragana, Katakana, and alphanumeric characters. For alphanumeric characters, you can enter uppercase and lowercase characters. Single-byte and double-byte characters can both be entered.

Searches can use the original spelling (with characters as they appear in materials). Searches can also use keywords converted into Roman alphabet letters using the ALA-LC Romanization Tables of the U.S. Library of Congress. Some materials are registered in Roman alphabet letters only. An index is created for them. So if the search has no hits with the original spelling, convert the keywords into Roman alphabet letters, and perform the search again.