Perhaps you should try some spelling variations:
vat xanh » vat thanh, sat anh, dat anh
so viet » hoc viet
ve cham » va cham, ve chat, vu cham
nang xa » nang x, lang xa, mang xa
xanh di » danh di, vanh dai, xanh tai
nang ma » tang ma, sang ma, nang cao
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
ve cai » va cai, ve cac, ve tai
di so » dai so, di o, di bo

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sac ky ((nang xa) or (nang ma)) hoi. hieu ((ve cai) or (ve cham)) thuc vat xanh di so viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky ((nang xa) OR (nang ma)) hoi. hieu ((ve cai) OR (ve cham)) thuc vat xanh di so viet.
• Adding a wildcard symbol may retrieve word variants: te sac ky ((nang xa) or (nang ma)) hoi. hieu ((ve cai) or (ve cham)) thuc vat xanh di so viet*.