diff --git a/app/controllers/api/doctrines_controller.rb b/app/controllers/api/doctrines_controller.rb
index 15b633a..18ddc72 100644
--- a/app/controllers/api/doctrines_controller.rb
+++ b/app/controllers/api/doctrines_controller.rb
@@ -59,6 +59,19 @@ module Api
       respond_with @doctrine
     end
 
+    def suggested_contents
+      @doctrines = []
+      search = doctrine_search(search_params.to_unsafe_h.merge({ is_grouped_by_content: true, per_page: 100000 }))
+
+      search.group(:content).groups.each do |group_by_content|
+        group_by_content.results.each do |result|
+          @doctrines << result
+        end
+      end
+
+      respond_with @doctrines
+    end
+
     private
 
       def resource_params
diff --git a/app/javascript/controllers/selectize_controller.js b/app/javascript/controllers/selectize_controller.js
index 6609c4b..3a19a0f 100644
--- a/app/javascript/controllers/selectize_controller.js
+++ b/app/javascript/controllers/selectize_controller.js
@@ -54,7 +54,7 @@ export default class extends ApplicationController {
         if (value.length === 0) {
           if ($selectize.length) $selectize[0].selectize.clearOptions();
         } else {
-          $.get("/api/doctrines.json", { subject_ids: value }, function(data, status) {
+          $.get("/api/doctrines/suggested_contents.json", { subject_ids: value }, function(data, status) {
             if (status === "success") {
               $.each(data, function (i, doctrine) {
                 selectize_options.push({ id: doctrine.id, value: doctrine.content, text: doctrine.plain_content });
diff --git a/app/views/api/doctrines/suggested_contents.json.jbuilder b/app/views/api/doctrines/suggested_contents.json.jbuilder
new file mode 100644
index 0000000..d5c23c8
--- /dev/null
+++ b/app/views/api/doctrines/suggested_contents.json.jbuilder
@@ -0,0 +1,3 @@
+json.array!(@doctrines) do |doctrine|
+  json.extract! doctrine, *%i[id subject_ids headnote content plain_content created_at updated_at]
+end
diff --git a/config/routes.rb b/config/routes.rb
index 5770f39..bb2ae43 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -33,6 +33,7 @@ Rails.application.routes.draw do
 
   namespace :api, defaults: { format: :json } do
     resources :doctrines do
+      get :suggested_contents, on: :collection
       scope module: :doctrine do
         resources :annotations do
           get :search, on: :collection