Text summarization is an important part of natural language processing. Currently, the methods used to summarize Vietnamese text are ineffective. In this paper, the authors present the use of document structure and a Vietnamese thesaurus dictionary to build a graphic link between sentences in order to summarize the text. Test results show, that structural methods are used more than a Vietnamese thesaurus with the threshold value of 0.2 for best results (the average F measure is 52.41 percent when using the approved method of depth-first search (DFS) based on the node degree to pick out the sentence. Summarization took place at an average speed of 8 minutes/50 documents with an average of 40 sentences/documents.