Perhaps you should try some spelling variations:
cau triet » cau trieu, su triet, cua triet
dang hai » dang khai, hang hai, dung hai
danh hai » lanh hai, manh hai, danh hau
hieu van » hieu va, thien van, lieu va
mai hoi » mai khoi, dai hoi, lai hoi
sach ly » sach y, sach lo, sach ty
nam tuc » nam thuc, nam truc, nam tu
ly nang » ky nang, ly hang, ly vang
bo sach » co sach, hoc sach
ma hoi » xa hoi, ma hoa, me hoi
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: bo sach ly nang ((ma hoi) or (mai hoi)). hieu van nam tuc va ((danh hai) OR (dang hai)) cau triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: bo sach ly nang ((ma hoi) OR (mai hoi)). hieu van nam tuc va ((danh hai) OR (dang hai)) cau triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "bo sach ly nang ((ma hoi) or (mai hoi)). hieu van nam tuc va ((danh hai) OR (dang hai)) cau triet".
• Adding a wildcard symbol may retrieve word variants: bo sach ly nang ((ma hoi) or (mai hoi)). hieu van nam tuc va ((danh hai) OR (dang hai)) cau triet*.