To link the search criteria with the products, you must create the search DB where the search combinations and the appropriate results should be specified. This allows you to configure the app to work the exact way you need it.
There are two options to create the search DB:
Option 1. directly in the app admin. Here, you may select the required products/collections/tags or URLs where our app will direct your customers. Just click the "Add model" link above the form on the Database page, and you'll see the form where you may add the search criteria and the results (https://ibb.co/wWS16dB).
Option 2. a CSV file with the required data you upload to the app (https://ibb.co/RcCGggp).
To point particular search terms combination to the corresponding list of products, you may use a list of SKUs or product handles in your CSV file or just a URL. In the case of URLs, here are also some good practices that may work for you (especially if you already have a similar catalog structure with properly tagged products):
a. You may create new collections for each search term. But this solution is not flexible and time-consuming as each time you add a new product, you'll need to add it to the proper collection manually;
b. You may tag each product with Make, Model, and Year tags (i.e. KTM, 350 MX, 1989) and create an automatic collection based on tag filters. It will work pretty similar to (1), but when you add a new product, it will be automatically added to the proper collection, so you'll save some time;
c. Tag products as described in (2) and filter products by tag. For example, in Shopify, you may use the following URLs: /collections/all/ktm+350-mx+1989. In this case, you won't need to spend time creating collections. All you need is properly tagged products. Or you may create collections for Make and filter them by model and year as tags - in this case, the URL will look fancier: /collections/ktm/350-mx+1989.
Of course, as our app allows you to use any URL, there are no limitations, and you may point some search terms to a particular product page, or just some landing page, and so on.
Besides, please note that the app won't be able to process files over 130 MB. Moreover, the problem with tag over the limit may occur as Shopify allows you to have only 250 tags per product.