You can create as many user-defined indexes as you want.
To Create a User-Defined Index
Select a word or words that you want to add to a user-defined index.Choose Insert - Table of Contents and Index - Index Entry.Click the New User-defined Index button next to the Index box.Type a name for the index in the Name box and click OK.Click Insert to add the selected word(s) to the new index.Click Close.
To Insert a User-Defined Index
Click in the document where you want to insert the index.Choose Insert - Table of Contents and Index - Table of Contents, Index or Bibliography.On the Type tab, select the name of the user-defined index that you created in the Type box.Select any options that you want.Click OK.