Perhaps you should try some spelling variations:
day thanh » dao thanh, dat thanh, da thanh
xay hanh » day nhanh, xanh hanh, xuan hanh
hieu van » hieu va, thien van, lieu va
cau treo » cau theo, cau tren, cau triet
te sac » te sach, te cac
te san » te ban, ke san, tu san
nam tu » nam thu, nam thuc
vi cau » va cau, ve cau, di cau

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