Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
day hanh » day nhanh, day thanh, dao hanh
thuc day » thuc dan, thuc vat
nam thuc » nam thuoc, am thuc, nam thu
tang van » dang van, hoang van, trong van
cua tre » cua te, cuu tre, dua tren
sach ky » sac ky, sach y, sach ty
vu sach » vu bach, su sach, vu khach
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va nam » van nam, ha nam, va nay

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky ((lang xa) or (tang van)) hoi. hieu va nam thuc day hanh vi ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky ((lang xa) OR (tang van)) hoi. hieu va nam thuc day hanh vi ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky ((lang xa) or (tang van)) hoi. hieu va nam thuc day hanh vi ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: vu sach ky ((lang xa) or (tang van)) hoi. hieu va nam thuc day hanh vi ((cua tre) OR (cua triet))*.