Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sinh dai » sinh thai, si dai, sinh vat
toc sach » hoc sach, doc sach, thuoc sach
han nang » phan nang, van nang, ban nang
cham tuc » nham thuc, pham thuc, tham thuc
hieu va » lieu va, hieu qua
va sinh » va kinh, va tinh, vi sinh
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu van
ma hoi » mai hoi, xa hoi, ma hoa
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: ((te sach) or (toc sach)) han nang ma hoi. ((hieu ve) OR (hieu va)) cham tuc va sinh dai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) han nang ma hoi. ((hieu ve) OR (hieu va)) cham tuc va sinh dai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) han nang ma hoi. ((hieu ve) OR (hieu va)) cham tuc va sinh dai cua triet".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) han nang ma hoi. ((hieu ve) OR (hieu va)) cham tuc va sinh dai cua triet*.