When searching for products, website visitors might type in a word that is too broad. This leads to irrelevant search results show up.
For example, a clothing store specialized in selling seasonal clothing that has many brands called Summer Trending Outfit, Winter Warm Outfit, Autumn Set Outfit, Casual Outfit, Classy Outfit, etc.
A customer type in the search box "summer trending outfit", it returns products that could possibly match either "summer", or "trending" or "outfit". This could bring out other brands (Winter Warm Outfit, Casual Outfit, etc) because it contains "outfit" word, which irrelevant to what the customer wants. Hence, excluding the word "outfit" from search returns better results and likely only results from the brand Summer Trending Outfit.