Perhaps you should try some spelling variations:
cau treo » cau theo, cau tren, cau triet
va khac » va khao, va kha, vu khac
thuc va » thuc vat, thuc dan, thuc day
cuu tre » cua tre, cau tren
va hac » van hac, va cac, va hoc
sac ky » cac ky, sai ky
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va
tu sac » tu sach, tu cac, tu san

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 x ho. hieu ((va hac) or (va khac)) thuc va dan vi ((cuu tre) OR (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang x ho. hieu ((va hac) OR (va khac)) thuc va dan vi ((cuu tre) OR (cau treo)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky nang x ho. hieu ((va hac) or (va khac)) thuc va dan vi ((cuu tre) OR (cau treo))".
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang x ho. hieu ((va hac) or (va khac)) thuc va dan vi ((cuu tre) OR (cau treo))*.