I am trying to only select the difference between
$query = mysql_query("SELECT * FROM `Posts` WHERE `isPublic` = 'yes' ORDER BY `date` DESC LIMIT $from,$to") or die(mysql_error());
Check this out: SELECT MySQL documentation.
What you are doing by
LIMIT 5, 10 is a synonym to
LIMIT 10 OFFSET 5 (get 10 results skipping 5 results from the beginning of the set returned by database).