How to restrict to content type in advanced search option?

Hi,

You should first visit the sphinxsearch settings page. There is a collaptible fieldset that allows you to select which content types you wish to index. You should also choose which taxonomy vocabularies you wish to index.

Changing those particular options require you to rebuild all indexes.

The advanced search form will then display all the options that have been enabled. The faceted search block will also display sections for content types and vocabularies as soon as data is indexed with proper options.

:-)