Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
doanh cua » doanh luan
nam thuc » nam thuoc, am thuc, nam thu
thai cua » than cua, tai cuc, tri cua
hieu van » hieu va, thien van, lieu va
nam duc » nam duoc, pham duc, nam buoc
cua hoa » cua khoa, cua hoi, cua hoc
va hanh » van hanh, va thanh, va danh
sac ky » sai ky
cua te » cua tu

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) OR (cac ky)) doanh cua hoa. hieu van ((nam duc) or (nam thuc)) va hanh thai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sac ky) OR (cac ky)) doanh cua hoa. hieu van ((nam duc) OR (nam thuc)) va hanh thai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sac ky) OR (cac ky)) doanh cua hoa. hieu van ((nam duc) or (nam thuc)) va hanh thai cua te".
• Adding a wildcard symbol may retrieve word variants: te ((sac ky) OR (cac ky)) doanh cua hoa. hieu van ((nam duc) or (nam thuc)) va hanh thai cua te*.