I add the below code and work fine now.

Dim objDoc As Document
Dim cBI As Style, cBIsub As Style, cBIsup As Style, cItalic As Style, cIsub As Style, cIsup As Style, cBold As Style, cBsub As Style, cBsup As Style, cSub As Style, cSup As Style, cAllCap As Style, cSmCap As Style
Set objDoc = ActiveDocument

Set cBI = ActiveDocument.Styles.Add("cBI", Type:=WdStyleType.wdStyleTypeCharacter)
Set cBIsub = ActiveDocument.Styles.Add("cBIsub", Type:=WdStyleType.wdStyleTypeCharacter)
Set cBIsup = ActiveDocument.Styles.Add("cBIsup", Type:=WdStyleType.wdStyleTypeCharacter)
Set cBold = ActiveDocument.Styles.Add("cBold", Type:=WdStyleType.wdStyleTypeCharacter)
Set cBsub = ActiveDocument.Styles.Add("cBsub", Type:=WdStyleType.wdStyleTypeCharacter)
Set cBsup = ActiveDocument.Styles.Add("cBsup", Type:=WdStyleType.wdStyleTypeCharacter)
Set cItalic = ActiveDocument.Styles.Add("cItalic", Type:=WdStyleType.wdStyleTypeCharacter)
Set cIsub = ActiveDocument.Styles.Add("cIsub", Type:=WdStyleType.wdStyleTypeCharacter)
Set cIsup = ActiveDocument.Styles.Add("cIsup", Type:=WdStyleType.wdStyleTypeCharacter)
Set cSub = ActiveDocument.Styles.Add("cSub", Type:=WdStyleType.wdStyleTypeCharacter)
Set cSup = ActiveDocument.Styles.Add("cSup", Type:=WdStyleType.wdStyleTypeCharacter)
Set cAllCap = ActiveDocument.Styles.Add("cAllCap", Type:=WdStyleType.wdStyleTypeCharacter)
Set cSmCap = ActiveDocument.Styles.Add("cSmCap", Type:=WdStyleType.wdStyleTypeCharacter)

and Help me how to find greek letters. I will do the remaining.