Some products donot display description

Hi,

That's because your characteristics are not setup properly in your product.
Before HikaShop 1.6.0, you had to add all the characteristics at once in a product, otherwise it would work properly.
So you need to:
1. Delete all the variants of the product on the listing of variants that you can access via the button "manage variants" on the product edition screen.
2. Delete the characteristics of the product.
3. Save the product.
4. Add the characteristics again.
5. The system will regenerate all the variants automatically and you should be able to see the dropdowns properly on the front end.