diff --git a/_config.production.yml b/_config.production.yml
index 9429a7c1..feac86a9 100644
--- a/_config.production.yml
+++ b/_config.production.yml
@@ -52,6 +52,11 @@ permalink: /:categories/:title.html
 
 # Search
 search: true
+search_type: docsearch  # "default", "docsearch" are supported.
+docsearch:
+  appId: SFGDUYE6XB
+  apiKey: 0f353764aa52c81dd2d893bc669b4f7b
+  indexName: lisz
 
 # MathJax
 mathjax: true
diff --git a/_config.tsukuba.yml b/_config.tsukuba.yml
index fb153950..92eedaa8 100644
--- a/_config.tsukuba.yml
+++ b/_config.tsukuba.yml
@@ -52,6 +52,11 @@ permalink: /:categories/:title.html
 
 # Search
 search: true
+search_type: docsearch  # "default", "docsearch" are supported.
+docsearch:
+  appId: SFGDUYE6XB
+  apiKey: 0f353764aa52c81dd2d893bc669b4f7b
+  indexName: lisz
 
 # MathJax
 mathjax: true
diff --git a/_config.yml b/_config.yml
index afe642f1..6264c63f 100644
--- a/_config.yml
+++ b/_config.yml
@@ -52,6 +52,11 @@ permalink: /:categories/:title.html
 
 # Search
 search: true
+search_type: docsearch  # "default", "docsearch" are supported.
+docsearch:
+  appId: SFGDUYE6XB
+  apiKey: 0f353764aa52c81dd2d893bc669b4f7b
+  indexName: lisz
 
 # MathJax
 mathjax: true