Below is xml file format from which words to be searched.
Preface
I would use Linq2Xml
XDocument xDoc = XDocument.Parse(xml); //or XDocument.Load(fileName)
var words = xDoc.Descendants("Word")
.Select(w => String.Join("",w.Descendants("Char").Select(c => c.Value)))
.ToList();
--EDIT--
for @Y.Ecarri
var words2 = xDoc.XPathSelectElements("//Word")
.Select(w => String.Join("", w.Elements().Select(c => c.Value)))
.ToList();