OpenXML C# read .docx

Попробуйте таким способом:

public string GetPlainText(OpenXmlElement element) 
{ 
    StringBuilder text = new StringBuilder(); 
    foreach (OpenXmlElement section in element.Elements()) 
    {              
        switch (section.LocalName) 
        { 
            // Text 
            case "t":  
                PlainTextInWord.Append(section.InnerText); 
                break; 
            case "cr":                          // Carriage return 
            case "br":                          // Page break 
                PlainTextInWord.Append(Environment.NewLine); 
                break; 
                // Tab 
            case "tab": 
                PlainTextInWord.Append("\t"); 
                break; 
            // Paragraph 
            case "p": 
                PlainTextInWord.Append(GetPlainText(section)); 
                PlainTextInWord.AppendLine(Environment.NewLine); 
                break; 
            default: 
                PlainTextInWord.Append(GetPlainText(section)); 
                break; 
        } 
    } 
    return text.ToString();
}
var text = GetPlainText(wordDocument.MainDocumentPart.Document.Body);                    
Console.WriteLine(text);

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