Some Unicode characters not displaying on Kindle

I am implementing a book for Kindle device using HTML, but some Unicode special characters are not displaying in Kindle, such as:

    X -hax: x&#772; 
    X-double bar : x&#x033F;
    R- hax : &#x035E;R

My head tag is :

<head>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
</head>

Please help me; how can I display the characters listed above (and shown below if your browser has sufficient Unicode support):

̿ U+033F COMBINING DOUBLE OVERLINE
͞ U+035E COMBINING DOUBLE MACRON
ݲ U+0772 ARABIC LETTER HAH WITH SMALL ARABIC LETTER TAH ABOVE

Solution

This might a be surprise, but not a single operating system includes fonts for every single Unicode code point.

Take Wikipedia's lead and embed images for unsupported glyphs.

A random example, the new Kazakhstani tenge currency symbol: ₸ vs. enter image description here

edit: It looks like there is little support for combining diacritics in PHP with GD/Freetype2 you have to look forward towards PHP6 or alternative method of producing them, such as GD with Pango:

https://bugs.php.net/bug.php?id=34670