There are a a few possible reasons this may occur;
1. When you add a new product to your admin panel, the system must create a cache of the product before it's placed into the search index. This may take up to 12 hours.
2. You may be searching only part of the word. Since the search tool indexes the product Title, listing/short description and keywords, it's not possible to run a partial word search as it would a) return way to many results and b) way too many unrelated or weak results. Whilst we may be able to prioritise these results, tests prove that the results were more unhelpful to customers than helpful.
3. It might be an obvious one, but double check your spelling on the product and the search phrase.
4. You may be using the wrong search option, such as "all of these words", when you have entered a word that doesn't match the product.
