Search in Japanese and Chinese
The following workaround was submitted by Andrea Robinson and verified by Quadralay.
While ePublisher Pro can generate output in a variety of languages, including double-byte character sets (e.g., Chinese, Japanese), several problems have been reported, including the lack of a working search feature. This issue can be resolved for Microsoft HTML Help 1.x output by generating the output on an operating system with same the language as the content.
That is, compile the CHM (either with ePublisher or HTML Help Workshop) on a Japanese OS, rather than an English OS with Japanese language support. Then, you can copy the CHM file back to your English system and use it—with full search capabilities—as desired.