does not search SKU numbers

I see on my website that if you know an SKU and search in search bar it will not find it

I believe that Searching SKU only works when on the Advanced Search page when Advanced / "Search In product descriptions" is selected.
If using 4.30 or under, if you know SQL, you can modify the ProductLoadAllPaged stored procedure as discussed here:
https://www.nopcommerce.com/en/boards/topic/29254/searching-product-with-sku-/page/2