Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
va tinh » may tinh
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
va nam » van nam, ha nam, va nay
vi va » vi van, vai va, bi va
vu va » vu van, tu va, su va

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 x ho. hieu va nam thuc ((va hanh) or (va tinh)) ((vi va) OR (vu va)) trien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky nang x ho. hieu va nam thuc ((va hanh) OR (va tinh)) ((vi va) OR (vu va)) trien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky nang x ho. hieu va nam thuc ((va hanh) or (va tinh)) ((vi va) OR (vu va)) trien".
• Adding a wildcard symbol may retrieve word variants: te sac ky nang x ho. hieu va nam thuc ((va hanh) or (va tinh)) ((vi va) OR (vu va)) trien*.