Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
cau treo » cau theo, cau tren, cau triet
dinh hai » dinh thai, tinh hai, dinh ha
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
vang xa » lang xa, mang xa, ang xa
ly vang » ly hang, ly van, ly quang
thuc va » thuc vat, thuc dan, thuc day
va dinh » van dinh, va kinh, va tinh
co sach » bo sach, cuon sach, hoc sach
su sach » so sach, vu sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (co sach)) ly vang xa hoi. hieu van nam thuc va dinh hai ((cau treo) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (co sach)) ly vang xa hoi. hieu van nam thuc va dinh hai ((cau treo) OR (su triet)).
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (co sach)) ly vang xa hoi. hieu van nam thuc va dinh hai ((cau treo) or (su triet))*.