Perhaps you should try some spelling variations:
nhanh hai » nhanh thai, thanh hai, nhanh ha
dau tren » dau tien, dat tren, dau tieng
hieu van » hieu va, thien van, lieu va
va nhanh » va thanh, va hanh, va nhan
cam thuc » am thuc, nam thuc, cam thu
van cam » van nam, van lam, van cau
thuc va » thuc vat, thuc dan, thuc day
su sach » so sach, vu sach
hai dau » han dau, hai dan, hai hau
tu cach » tu cac
ma hoi » mai hoi, xa hoi, me hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cach) or (su sach)) ky nang ((ma hoi) or (ma hoa)). hieu van cam thuc va nhanh hai dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (su sach)) ky nang ((ma hoi) OR (ma hoa)). hieu van cam thuc va nhanh hai dau tren.
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (su sach)) ky nang ((ma hoi) or (ma hoa)). hieu van cam thuc va nhanh hai dau tren*.