If some products does not display in search results page, chances are, you have a lot of options in your category tree and it's too long to display all of the products.
A category tree (available for BigCommerce only), also known as a structure, is a way to organize and classify products, services, or information into a hierarchical structure based on their characteristics, attributes, or relationships.
A category tree typically starts with a broad top-level category, which is then subdivided into more specific subcategories. Each subcategory can further branch out into additional subcategories, creating a hierarchical structure that allows for easy navigation and classification of products or information.
HOW CAN THIS BE RESOLVED?
This can be rectified by disabling the Full Category Tree Filter option.
You can do this by going to your:
1. Dashboard
2. Collections
3. Configuration
4. Disable Full Category Tree Filter:
Another solution is to switch your search and collection page to the V-Next version and get the feature to have the filters collapsed on page load.