Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
danh vai » danh sai, doanh van, dang van
hieu van » hieu va, thien van, lieu va
toc sach » hoc sach, doc sach, thuoc sach
hoa lang » hoa dan, hoa van
lam duc » lam duoc, pham duc, nam duoc
danh va » doanh va, hanh va, anh va
van lam » van nam
o lang » hoi lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((o lang) OR (hoa lang)) ha noi. hieu van lam duc va ((danh vai) or (danh va)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((o lang) OR (hoa lang)) ha noi. hieu van lam duc va ((danh vai) OR (danh va)) cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((o lang) OR (hoa lang)) ha noi. hieu van lam duc va ((danh vai) or (danh va)) cua triet".
• Adding a wildcard symbol may retrieve word variants: toc sach ((o lang) OR (hoa lang)) ha noi. hieu van lam duc va ((danh vai) or (danh va)) cua triet*.