Perhaps you should try some spelling variations:
cach thoi » cac thoi, cach thuc, cach noi
thoi nang » thi nang, hoi nang, khoi nang
thien van » thi van
khanh di » khanh bui, khanh duy, thanh doi
thuc dan » thuc hanh, thuc vat
tu cach » tu cac
ca viet » va viet, co viet, hoa viet
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
di ca » di cau, di cua, doi ca

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 thoi nang ma hoi. ((thien van) or (hieu va)) nam ((thuc dan) or (hoc dan)) khanh di ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cach thoi nang ma hoi. ((thien van) OR (hieu va)) nam ((thuc dan) OR (hoc dan)) khanh di ca viet.
• Adding a wildcard symbol may retrieve word variants: tu cach thoi nang ma hoi. ((thien van) or (hieu va)) nam ((thuc dan) or (hoc dan)) khanh di ca viet*.