magento2 – The quick search for Magento 2.2.6 does not work sometimes

I try to search for a product through a quick search using the product name and its brand name.

But that does not work for all products. Only for some products.

For example, if I search products of the brand "XYZ", the result is displayed. But when I search products of the brand "ABC", it shows me a message "Your search did not produce any results."

I've checked at Marketing >> SEO & Search >> Search Terms

So, it displays the result counts 0 for that particular term.

Am I missing something here?