Subject—BrowseNode IDs of all topics related to items returned by ItemSearch. For example, searching for books about dogs returns, in the Subject bins, BrowseNodes for "Home & Garden," "Animal Care & Pets," "Dogs," and "Educational."
BrandName—Brands, such as Levi's, Reebok, and Nike, that create the item. Use the name of a brand to filter out similar items made by other companies.
PriceRange—Minimum and maximum prices for a bin of items. Use the minimum and maximum price values in each bin to filter out items outside of the price range you want.
SpecialSize—Uncommon sizes an item comes in. Examples are "Plus Size & Tall," "Misses," "Maternity," "Husky," "Petites," and "Big & Tall."
Merchant—All merchants selling an item. This bin returns all merchants even if MerchantId is set to a single merchant in the ItemSearch request. In the response, the ASINs returned will be specific to the MerchantId specified in the request. The merchants listed in the Merchant bin can be used to list other merchants that sell the same ASIN. There are some items sold by only one merchant. In that case, the Merchant bin returns with only that merchant.
All search indices return the Subject bin. Most return all of the bins.