Website Search Functionality For 2 Million Products

I have an Ecommerce/Online Shopping site with around 2 million items(MS SQL Server DB). It has various products and i want to implement a search functionality for it. The search could be anything like "White shirt" , "Black Shoes", "Leather Belt" so on.

How do i implement the search mechanism ? The site is expected to grow in years.

I know solutions like SQL free-text, Full-text search.

but which one would be appropriate for the scenario. You know people search weird things ?

CURRENT PROBLEM: If a user search "White Shirt" than I search this item from database 5 to 6 times. First search will load the results in website products list. Other searches will get the item count for different search filters.

1. First search will get the item for website search body.
2. Second search will get the counts for discount filter like 5%, 10% or 50%...