Viewing Usage of Aliases 
You can check in which If-Then rule or Decision Table, the aliases have been used.
In the Project/Ruleset Aliases Editor, in Alias Name table choose an alias and choose the Show Usage button.
In the Usage dialog box that appears, you can view the below message
Please look at 'Rule Location View' For Usage — If the alias is being used in the ruleset.
No usage found — If the alias is not being used in the ruleset.
Choose OK.
You can view the Rule Location View
Note
If the Rule Location View is not open:
In the Developer Studio, choose
In the screen that appears, expand Rules and choose Rule Location View.