Hello EN KEN，
Thank you for posting in our Q&A forum.
The auto-suggest box is a control that includes a search function, an input field that suggests words based on the search terms you have typed so far.
A Custom Search Engine searches a set of sites that you specify. However, you can configure a Custom Search Engine to search the entire web.
The exact function of the title bar and the options available for customizing it depend on the UI platform and application requirements:
Hope above information can help you.
And when a search is performed using the Autosuggest box and no search results exist for the text entered, a single-line "No Results" message is displayed as the result so that the user knows that their search request was executed
Thanks a lot!