CompositeNode.GetChildNodes method returns a collection of child nodes that match the specified type. Please use Document.GetChildNodes method with NodeType.Shape to get the images of document and NodeType.Table to get the tables of document.
NoteType.OfficeMath is used for Office Math object. Can be equation, function, matrix or one of other mathematical objects. Can be a collection of mathematical object and also can contain some non-mathematical objects such as runs of text.
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