dig.do is now able to index sites using many character sets and distinct alphabets.
Example of some common character sets used by international websites:
Charset UTF-8 and Unicode: Unicode is now the standard for all International alphabets.
Charset ISO-8859-1 (Latin-1): ISO8859-1 was the main character set for ocidental languages before Unicode
Charset windows-1254: Code page to write Turkish characters.
Charset windows-1251: Code Page 1251 or CP1251 is the cyrillic alphabet used by sites in Russia and Bulgaria for example
Charset gbk and gb2312: GB means Guojia Biaozhun (National Standard, in Chinese). It's the encoding character set for Chinese language.
Charset shift_jis: Shift JIS is a character encoding for the Japanese language
Charset Big5: Character encoding for Chinese language (traditional Chinese characters).