Knowledge search function does not work for Traditional Chinese characters if the parse settings are set to language = English.
To perform a search using Traditional Chinese characters, you must use the following Parse Settings:
Language = "Other Far East"
Valid Character Range = a-z
Language = "Other Far East" - indexes character by character because according to the Chinese linguistic rules, each Chinese character can represent a word and each word may not be separated by a space as it can in English language.