[Bug]: Searching a single digit in the site's global search crashes with a server error

Description:

The website has a global search box in the header that lets a visitor search across the site, including their account information like purchase orders. Typing a short, common search term like a single digit crashes the page instead of showing results.

Steps to Reproduce:

1. Go to the site's front end and open the global search box in the header.
2. Type a single digit, such as "4".
3. Submit the search.

Actual Behaviour:

The page shows an Internal Server Error (LogicException: "The resource ... does not have an [index] page. Define [getIndexUrl()] for alternative routing."). No search results are shown.

Expected Behaviour:

Searching a single digit (or any other valid search term) should return matching results normally, without crashing the page. If there are no results, it should say so instead of throwing an error.

Screenshot: