public void ClearContent(
    PdfClearContentRegions regions,
    PdfClearContentOptions options
)

Public Sub ClearContent(
    regions As PdfClearContentRegions,
    options As PdfClearContentOptions
)

using (PdfDocumentProcessor pdfDocumentProcessor = new PdfDocumentProcessor())
{
    // Load a document
    pdfDocumentProcessor.LoadDocument("Document.pdf");
    PdfClearContentRegions contentRegions = new PdfClearContentRegions();

    // Find the target phrase in the document
    string removeText = "Ounce";

    PdfTextSearchParameters searchParameters = new PdfTextSearchParameters()
    {
       WholeWords = true
    };

    PdfTextSearchResults searchResults = pdfDocumentProcessor.FindText(removeText, searchParameters);

    while (searchResults.Status == PdfTextSearchStatus.Found && searchResults.PageNumber == 1)
    {
        // Add text rectangles to the region collection:
        contentRegions.Add(searchResults.Rectangles);
        searchResults = pdfDocumentProcessor.FindText(removeText, searchParameters);
    }

    // Get the first page properties
    PdfPageFacade pageFacade = pdfDocumentProcessor.DocumentFacade.Pages[0];

    // Specify what content type to keep in target areas
    PdfClearContentOptions options = new PdfClearContentOptions()
    {
        ClearAnnotations = false,
        ClearGraphics = false,
        ClearImages = false
    };

    // Remove found entries
    pageFacade.ClearContent(contentRegions, options);

    // Save the result
    pdfDocumentProcessor.SaveDocument("Document_cleared.pdf");
}

Using pdfDocumentProcessor As New PdfDocumentProcessor()
  ' Load a document
  pdfDocumentProcessor.LoadDocument("Document.pdf")

  Dim contentRegions As New PdfClearContentRegions()

  ' Find the target phrase in the document
  Dim removeText As String = "Ounce"
  Dim searchParameters As New PdfTextSearchParameters() With {.WholeWords = True}
  Dim searchResults As PdfTextSearchResults = pdfDocumentProcessor.FindText(removeText, searchParameters)

  Do While searchResults.Status = PdfTextSearchStatus.Found AndAlso searchResults.PageNumber = 1
    ' Add text rectangles to the region collection:
    contentRegions.Add(searchResults.Rectangles)
    searchResults = pdfDocumentProcessor.FindText(removeText, searchParameters)
  Loop

  ' Get the first page properties
  Dim pageFacade As PdfPageFacade = pdfDocumentProcessor.DocumentFacade.Pages(0)

  ' Specify what content type to keep in target areas
  Dim options As New PdfClearContentOptions() With
     {.ClearAnnotations = False, .ClearGraphics = False, .ClearImages = False}

  ' Remove found entries
  pageFacade.ClearContent(contentRegions, options)

  ' Save the result
  pdfDocumentProcessor.SaveDocument("Document_cleared.pdf")
End Using