diff --git a/docs/usage.rst b/docs/usage.rst
index ab05952..b4ceae0 100644
--- a/docs/usage.rst
+++ b/docs/usage.rst
@@ -327,7 +327,8 @@ post_data_type
   (*Optional*) Specifies the ``Content-Type`` of the request body (``post_data``). By default, this is ``application/x-www-form-urlencoded``.
 
 .. note::
-  An additional dependency "lxml" is required.
+   An additional dependency "lxml" is required.
+   You can use ``pip install 'nvchecker[htmlparser]'``.
 
 Find with a Command
 ~~~~~~~~~~~~~~~~~~~
@@ -536,6 +537,10 @@ pypi
 use_pre_release
   Whether to accept pre release. Default is false.
 
+.. note::
+   An additional dependency "packaging" is required.
+   You can use ``pip install 'nvchecker[pypi]'``.
+
 Check RubyGems
 ~~~~~~~~~~~~~~
 ::
@@ -874,6 +879,9 @@ strip_release
 provided
   Instead of the package version, return the version this package provides. Its value is what the package provides, and ``strip_release`` takes effect too. This is best used with libraries.
 
+.. note::
+   An additional dependency "pyalpm" is required.
+
 Check ALPM files database
 ~~~~~~~~~~~~~~~~~~~~~~~~~
 ::