No, you can simply use the MySQL LIKE operator to perform a basic search (e.g. title contains "stackoverflow", etc...), or more preferably use the MyISAM storage engine that has fulltext search capabilities.
See the manual for more information about fulltext index and searches : http://dev.mysql.com/doc/refman/5.0/en/fulltext-search.html
But AFAIK, nothing prevents you from uploading the Zend Framework yourself, and use it as usual. The only thing is that you may not be able to write files out of your apache directory (which is required for a standard zend framework folder structure), so check this article on how to set ZF up on a shared hosting.