Which would be best ecommerce Wordpress theme for online bookstore?

Please suggest some best Wordpress themes for an online bookstore which has an advance search feature.

Any of these would be good - there are some very reputable and respected authors in there too https://themeforest.net/category/wordpress?term=bookstore#content

Depending on the complexity of the search that you require - this may need to be extended using plugins or custom development.