You can configure the Case Deflection widget to allow the customers to search the solution. You need to configure the following details:
Description: Insert the relevant message to search the solution.
Redirect Page: Select the specific redirection page. i.e., Create Case page
Records Per Page: Set the no. of records to be displayed on the page.
Design Layout: By scrolling down, you will get the 2-predefined Design Layouts to select the appearance of the case deflection in the customer portal.