Perhaps you should try some spelling variations:
"thuat quan lang." » "thuat san lang." (Expand Search), "thuat cua lang." (Expand Search), "thuat quan long." (Expand Search), "thuat gian lang." (Expand Search), "thuat quan dong." (Expand Search)
"thuat than lang." » "thuat thang lang." (Expand Search), "thuat thanh lang." (Expand Search), "thuat phan lang." (Expand Search), "thuat tham lang." (Expand Search)
"thuat toan lang." » "thuat trang lang." (Expand Search), "thuat dan lang." (Expand Search), "thuat tai lang." (Expand Search), "thuat tan lang." (Expand Search), "thuat ton lang." (Expand Search), "thuat toan lanh." (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: (("thuat quan lang.") OR ((("thuat than lang.") OR ("thuat toan lang."))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"thuat quan lang.\") OR (((\"thuat than lang.\") OR (\"thuat toan lang.\"))))".
• Removing quotes may allow a broader search: (( thuat quan lang. ) OR ((( thuat than lang. ) OR ( thuat toan lang. )))).
• Adding a wildcard symbol may retrieve word variants: (("thuat quan lang.") OR ((("thuat than lang.") OR ("thuat toan lang."))))*.