this is code in my indices file
ThinkingSphinx::Index.define 'cg_user/user', :name => 'reviewer_search', :with => :active_record, :delta => true do
indexes profile.interests.interest_name, :as => :interest_name
has profile(:voluntary_reviewer), as: :profile_voluntary_reviewer, :type=>:boolean
has id, :as => :user_id
set_property :field_weights => { :interest_name => 3 }
end
this is my condtion in model
CgUser::User.search(search_string,
:with => {:profile_voluntary_reviewer => true,
:user_id => probable_matched_name_ids},
:indices => ['reviewer_search_core',
'reviewer_search_delta']
).map(&:id).compact