http://cathalscorner.blogspot.hk/2010/06/cathal-why-did-you-create-docx.html
using (DocX document = DocX.Load(@"C:\source\3.docx"))
{
Formatting mFormatting=new Formatting();
document.ReplaceText("«bbbb»", "bbbaaaaaaaaaaa",
false, RegexOptions.Singleline, null, null, MatchFormattingOptions.ExactMatch, true, true);
document.Save();
}
