fix readme

README.md

@@ -53,7 +53,7 @@ You may need to use a domestic mirror source (in China, you can use the Tsinghua
 
 If you need install modules compiled with develop branch, please download packages from [latest packages list](./doc/LATEST_PACKAGES.md) and install with `pip install` command.
 
-Client package support Centos 7 and Ubuntu 18, or you can use HTTP service without install client.
+Paddle Serving support Centos 6/7 and Ubuntu 16/18, or you can use HTTP service without install client.
 
 
 <h2 align="center"> Pre-built services with Paddle Serving</h2>

README_CN.md

@@ -55,7 +55,7 @@ pip install paddle-serving-server-gpu # GPU
 
 如果需要使用develop分支编译的安装包，请从[最新安装包列表](./doc/LATEST_PACKAGES.md)中获取下载地址进行下载，使用`pip install`命令进行安装。
 
-客户端安装包支持Centos 7和Ubuntu 18，或者您可以使用HTTP服务，这种情况下不需要安装客户端。
+Paddle Serving 支持Centos 6/7和Ubuntu 16/18，或者您可以使用HTTP服务，这种情况下不需要安装客户端。
 
 <h2 align="center"> Paddle Serving预装的服务 </h2>