Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
luc tieng » hoc tieng
tu tieng » tu tuong, tu trong
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
thuc va » thuc vat, thuc dan, thuc day
han tai » hang tai, nhan tai, van tai
te sai » te tai, te bai, te lai
sai ky » sac ky
ma hoi » mai hoi, xa hoi, ma hoa
va han » va phan, van han, va hanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sai ky nang ma hoi. hieu ve cham thuc va han tai ((tu tieng) or (luc tieng))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sai ky nang ma hoi. hieu ve cham thuc va han tai ((tu tieng) OR (luc tieng)).
• Adding a wildcard symbol may retrieve word variants: te sai ky nang ma hoi. hieu ve cham thuc va han tai ((tu tieng) or (luc tieng))*.