Perhaps you should try some spelling variations:
va doanh » van doanh, vay doanh, hoa doanh
su triet » su viet, su tien, ve triet
nang ma » tang ma, sang ma, nang cao
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va danh » va dinh, va dan, va hanh
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
va cao » va cac, va co, va dao
cao tu » cao thu, co tu, cao su

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 ((nang ma) or (lang xa)) hoi. hieu va cao tu ((va doanh) or (va danh)) va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang ma) OR (lang xa)) hoi. hieu va cao tu ((va doanh) OR (va danh)) va su triet.
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang ma) or (lang xa)) hoi. hieu va cao tu ((va doanh) or (va danh)) va su triet*.