Perhaps you should try some spelling variations:
dat thanh » dao thanh, dat khanh, dang thanh
thuc dat » thuc vat, thuc dan, thuc day
nam thuc » nam thuoc, am thuc, nam thu
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
co sach » bo sach, cuon sach, hoc sach
te sach » toc sach
ma hoi » mai hoi, xa hoi, ma hoa
va nam » van nam, ha nam, va nay
vi cau » va cau, di cau, viet cau
ve cau » ke cau, va cau, ve cac

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 (co sach)) ky nang ma hoi. hieu va nam thuc dat thanh ((vi cau) OR (ve cau)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (co sach)) ky nang ma hoi. hieu va nam thuc dat thanh ((vi cau) OR (ve cau)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (co sach)) ky nang ma hoi. hieu va nam thuc dat thanh ((vi cau) OR (ve cau)) triet".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (co sach)) ky nang ma hoi. hieu va nam thuc dat thanh ((vi cau) OR (ve cau)) triet*.