Perhaps you should try some spelling variations:
phan thuc » nhan thuc, phap thuc, pham thuc
hieu ve » hieu va, hieu van
doan vi » doan va, don vi, doan thi
va doan » va doanh, van doan, va dan
thuc va » thuc vat, thuc dan, thuc day
ve phan » va phan, ke phan, ve phat
cua tre » cua te, cuu tre, cua triet
mai hoi » mai khoi, dai hoi, lai hoi
ky sang » ky nang, ky dang, ky tang
sac ky » cac ky, sai ky
ma hoi » xa hoi, me hoi, va hoi
vi cua » vai cua, di cua
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky sang ((((ma hoi) OR (mai hoi))) or (ma hoa)). hieu ve phan thuc va doan vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky sang ((((ma hoi) OR (mai hoi))) OR (ma hoa)). hieu ve phan thuc va doan vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky sang ((((ma hoi) OR (mai hoi))) or (ma hoa)). hieu ve phan thuc va doan vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sac ky sang ((((ma hoi) OR (mai hoi))) or (ma hoa)). hieu ve phan thuc va doan vi cua tre*.