What are the names of the vendors to which the company purchased its women's tights products?
product is purchased refers to MakeFlag = 0; women's refers to Style = 'W'; ProductSubcategoryID = 'Tights';
SELECT DISTINCT T4.Name FROM Product AS T1 INNER JOIN ProductVendor AS T2 ON T1.ProductID = T2.ProductID INNER JOIN ProductSubcategory AS T3 ON T1.ProductSubcategoryID = T3.ProductSubcategoryID INNER JOIN Vendor AS T4 ON T2.BusinessEntityID = T4.BusinessEntityID WHERE T1.MakeFlag = 0 AND T1.Style = 'W' AND T3.Name = 'Tights'