#１　日本語のUTF-8に設定

[hoge@sakura ~]# localectl set-locale LANG=ja_JP.utf8

#２　再読み込みさせて設定を反映

[hoge@sakura ~]# source /etc/locale.conf

１だけでは日本語UTF-8にならない為、このコマンドで設定を有効にします。localectlは有効オプションがない為locale.confを再読み込みする事で反映させます。localectlで設定したロケールは、/etc/locale.confに反映されます。

#３　確認其の１　cat /etc/locale.conf

[hoge@sakura ~]# cat /etc/locale.conf
LANG=ja_JP.utf8

#４　確認其の２　localectl status

[hoge@sakura ~]# localectl status
   System Locale: LANG=ja_JP.utf8
       VC Keymap: jp106
      X11 Layout: jp

#５　確認其の３　locale

[hoge@sakura ~]# locale
LANG=ja_JP.utf8
LC_CTYPE="ja_JP.utf8"
LC_NUMERIC="ja_JP.utf8"
LC_TIME="ja_JP.utf8"
LC_COLLATE="ja_JP.utf8"
LC_MONETARY="ja_JP.utf8"
LC_MESSAGES="ja_JP.utf8"
LC_PAPER="ja_JP.utf8"
LC_NAME="ja_JP.utf8"
LC_ADDRESS="ja_JP.utf8"
LC_TELEPHONE="ja_JP.utf8"
LC_MEASUREMENT="ja_JP.utf8"
LC_IDENTIFICATION="ja_JP.utf8"
LC_ALL=

#６　確認其の４　最終確認として日本語出力の確認

[root@]# hoge
bash: hoge: コマンドが見つかりません

bash: hoge: command not found

Lastly,I had changed the error that I above & keywords Japanese from English including several files like log or txt's content within 2 min..That's it.