hi,
will below code snippet work for you? More deatils you chech the article- [Spam link removed]
Document document = new Document();
document.LoadFromFile(@"sample file");
TextSelection[] text = document.FindAllString("vs", false, true);
foreach (TextSelection seletion in text)
{
seletion.GetAsOneRange().CharacterFormat.HighlightColor = Color.Yellow;
}
document.SaveToFile("FindHighlight.docx", FileFormat.Docx);
System.Diagnostics.Process.Start("FindHighlight.docx");