How about
Code:
Sub FindHighlightWord()
Dim oRng As Word.Range
Dim vWords As Variant
Dim i As Long
Dim strWords As String
strWords = InputBox(Prompt:="Enter the words to highlight separated by commas", _
Title:="Highlight words", _
Default:="Friend,MITS,ICMR")
vWords = Split(strWords, ",")
For i = 0 To UBound(vWords)
Set oRng = ActiveDocument.Range
With oRng.Find
.ClearFormatting
.Replacement.ClearFormatting
Do While .Execute(FindText:=Trim(vWords(i)), _
MatchWholeWord:=True) = True
oRng.HighlightColorIndex = wdBrightGreen
oRng.Collapse 0
Loop
End With
Next
lbl_Exit:
Set oRng = Nothing
Exit Sub
End Sub