Perhaps you should try some spelling variations:
cau treo » cau theo, cau tren, cau triet
cham hoc » cham soc, chat hoc, cham hoi
cuu tre » cua tre, cau tren
va cham » va chat, va tham
hieu va » lieu va, hieu qua
lang ha » long ha
lang xa » dang xay, lang van
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 ((lang xa) or (lang ha)) hoi. hieu va cham hoc va dan vi ((cuu tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((lang xa) OR (lang ha)) hoi. hieu va cham hoc va dan vi ((cuu tre) OR (cau treo)).
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((lang xa) or (lang ha)) hoi. hieu va cham hoc va dan vi ((cuu tre) or (cau treo))*.