Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
van chet » van chat, van chuyet, van chien
chet duc » chet duoc, viet duc, che duoc
te sach » toc sach
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo
sach v » sach va, sach y, sach 2

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach v ((nang xa) or (lang xa)) hoi. hieu van chet duc va hanh vi ((cuu tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach v ((nang xa) OR (lang xa)) hoi. hieu van chet duc va hanh vi ((cuu tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: te sach v ((nang xa) or (lang xa)) hoi. hieu van chet duc va hanh vi ((cuu tre) or (cua triet))*.