diff --git a/lib/plugins/acts_as_searchable/lib/acts_as_searchable.rb b/lib/plugins/acts_as_searchable/lib/acts_as_searchable.rb
index ff9d2d507..fe0f8518e 100644
--- a/lib/plugins/acts_as_searchable/lib/acts_as_searchable.rb
+++ b/lib/plugins/acts_as_searchable/lib/acts_as_searchable.rb
@@ -87,10 +87,7 @@ module Redmine
             token_clauses = columns.collect {|column| "(LOWER(#{column}) LIKE ?)"}
 
             if !options[:titles_only] && searchable_options[:search_custom_fields]
-              searchable_custom_field_ids = CustomField.find(:all,
-                                                             :select => 'id',
-                                                             :conditions => { :type => "#{self.name}CustomField",
-                                                                              :searchable => true }).collect(&:id)
+              searchable_custom_field_ids = CustomField.where(:type => "#{self.name}CustomField", :searchable => true).pluck(:id)
               if searchable_custom_field_ids.any?
                 custom_field_sql = "#{table_name}.id IN (SELECT customized_id FROM #{CustomValue.table_name}" +
                   " WHERE customized_type='#{self.name}' AND customized_id=#{table_name}.id AND LOWER(value) LIKE ?" +