In a new installation, there is only one type of search installed. This is called "DB Search" and is an indexed implementation of Fulltext Search allowing you to search all content types marked as "Searchable" when they are created/installed in your system.
You can find alternative search engines from third-party vendors or possibly at https://www.vbulletin.org.
Note:
Changing search implementations will require you to rebuild the search index before the search function will return results. This can be done via Maintenance > Update Counters. Reindex can take a long time for large boards. Some high performance search engines may provide a faster alternate method of doing a full reindex, consult the documentation provided with your search type.