As they click into the search box…
a good practice is to show their previous search history, and possibly popular searches.
As they start typing…
You can show suggested searches, categories, and/or products.
Mispellings
The auto-suggestions and results should account for common misspellings. For example, if they type ‘dreses’ it should suggest results for ‘dresses’, and so on. You can also add the possibility for users to clear their search history.
Shopify Apps
There are several apps that do things like that. Go to apps.shopify.com and search for things like ‘recent searches’, ‘previous searches’, ‘popular searches’, ‘search’,… For example, there are:
Additional thoughts
From one of the members of my Ecom Convert group:
Just be aware that not all 3rd party search engines are very good, especially on WordPress. Shopify vets their plug-ins. We generally recommend InstantSearch+ for those just testing out a 3rd party or on a lower budget.
SearchSpring which has now merged with Nextopia, the two best search engines on the market, are amazing tools!
There is so much more you can do with these than with cheaper tools including completely customize the results. Little niceties like setting it to go straight to the product if there’s only one response. Choosing the order of the results, adding synonyms and generic phrases, and even directing obsolete items to their replacements. Plus you can add search result specific banners such as a sale on a brand or category. Well worth the higher price if you have good search volume (a brand new store generally won’t).