In the sidebar
In the site header
The OWT CMS can be configured to allow all site content to be searched. You can have a search configured just for products or maybe just a company directory or include all site content in one big search. Tags are utilized in the administration tools to help provide meaningful autocomplete options for searches to help guide the user to their desired content.
Any table of data can have a filter search that function to exclude content that does not match by hiding that content. Other search tools can be placed in the sidebar or header or above a directory to make searching easy for the user to understand as well as powerful.