Technically, you can't "sand off" the particles, as far as I know. They're embedded in the coverstock.
You can sand the cover to very fine, like 4000 grit Abralon and then apply either a regular polish or a polish that reduces the backend, like Valentino's UFO (or Track Delayed Reaction). They're reduce the overall hook, add lenth and reduce the backend.
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"None are so blind as those who will not see."