diff --git a/README.md b/README.md
index cc76f34..3b227f0 100644
--- a/README.md
+++ b/README.md
@@ -6,10 +6,18 @@ Fuzzy find your way to the configuration option you're searching for.
 
 
 ## Usage
+search all options from `hdfs-site.xml`:
+```bash
+hdfshelper -m hdfs
 ```
-TBA
+
+copy the output to clipboard (macOS):
+```bash
+hdfshelper -m core | pbcopy
 ```
 
+You can select more than one option to print with `<TAB>`.
+
 ## Supports
 Currently the options below are supported. 
 
diff --git a/main.go b/main.go
index ea3afeb..772fcd7 100644
--- a/main.go
+++ b/main.go
@@ -51,7 +51,7 @@ func main() {
         - hdfs [hdfs-site.xml]`
 	)
 	flag.StringVar(&mode, "mode", defaultMode, usageMode)
-	flag.StringVar(&mode, "m", defaultMode, usageMode)
+	flag.StringVar(&mode, "m", defaultMode, usageMode+"(shorthand)")
 
 	flag.Parse()