When you use some Korean characters (DBCS) to search contacts in a Lync client, the last character is not used for searching. Therefore, you receive many unnecessary search results. For example, if you type three Korean characters such as "홍길동" to search for a contact, contacts with the first two characters (홍길) are displayed instead of only those contacts who have all three characters (홍길동) in their names.
This issue does not affect non-Korean characters.
To work around this issue, press Enter or type a space after the last character (such as "홍길동 ") to include all Korean characters in your search.