'Create the Word Object
Set word_app = CreateObject("Word.Application")
Set word_doc = word_app.Documents.Open("C:\wrd.doc")
str_to_search = "QTP"
For p = 1 To word_doc.Paragraphs.Count
'A Range object represents a contiguous area in a document, defined by a starting character position and an ending character position. The contiguous area can be as small as the insertion point or as large as the entire document. It can also be, but does not have to be, the area represented by the current selection.
'When you use the Range method to specify a specific area of a document, you use the method's Start argument to specify the character position where the range should begin and you use the End argument to specify where the range should end.
'Using the Start and End properties with a Range object, you can create a new Range object that refers to a group of document elements.
startext_range = word_doc.Paragraphs(p).Range.Start
endRange = word_doc.Paragraphs(p).Range.End
Set text_range = word_doc.Range(startext_range, endRange)
text_range.Find.Text = str_to_search
'Performs a search based on the options set for the Find object.
If text_range.Find.Found Then
msgbox str_to_search & " is found"
'close the document
'close the Word application
Set word_doc = Nothing
Set word_app = Nothing
Also see Word Object Model Overview here