Active Admin allows me to define filters that are displayed on the index page like so:
ActiveAdmin.register Promo do
filter :name
filter :address
filt
Active Admin uses the meta_search gem for its filters. ORed conditions syntax allows to combine several fields in one query, for example
Promo.metasearch(:name_or_address_contains => 'brooklyn')
In Active Admin DSL this translates to
ActiveAdmin.register Promo do
filter :name_or_address, :as => :string
end