Try to use within the search block:
@search = Product.search do |query|
query.paginate page: page, per_page: per_page
end
You do not need to use the query variable in the block. You can invoke methods directly within the block.
@search = Product.search do
fulltext params[:sSearch]
with(:store_id, @store.id)
paginate page: page, per_page: per_page
end