Perhaps you should try some spelling variations:
"tran van giang." » "tran va giang." (Expand Search), "tran tuan giang." (Expand Search), "tran tran giang." (Expand Search), "luan van giang." (Expand Search), "san van giang." (Expand Search)
"tran bac giang." » "tran bai giang." (Expand Search), "tran bach giang." (Expand Search), "tran ba giang." (Expand Search), "tran bao giang." (Expand Search)
"tran bo giang." » "tran bai giang." (Expand Search), "tran ha giang." (Expand Search), "tran _ giang." (Expand Search), "tran bao giang." (Expand Search), "tran ba giang." (Expand Search), "tran do giang." (Expand Search)

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("tran van giang.") OR ((("tran bac giang.") OR ("tran bo giang."))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"tran van giang.\") OR (((\"tran bac giang.\") OR (\"tran bo giang.\"))))".
• Removing quotes may allow a broader search: (( tran van giang. ) OR ((( tran bac giang. ) OR ( tran bo giang. )))).
• Adding a wildcard symbol may retrieve word variants: (("tran van giang.") OR ((("tran bac giang.") OR ("tran bo giang."))))*.