This is Elias from Shopify Support. I'd be happy to lend a hand with this!
Alternatively, you can also use a third-party smart search app, which offers functions like predictive search, autocomplete, spell correction, and much more. Aside from being easier to work with compared to coding, the app developers are always available to help as well. If you need any help with an app, you can reach out to developer through the contact information found in the Support section of their app's page.
I noticed that your store doesn't have any store policies (eg. shipping or refund policies) on your navigation menus. This is something I'd recommend, as these resources can help address customer concerns and reduce the amount of customers that may otherwise be contacting your store. I've also noticed that you have some products on sale; however, this wasn't easily noticed. Have you thought about featuring some products on your homepage? Or, creating a sale collection for your menus?