Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
dang xay » dang van, van xay
hieu van » hieu va, thien van, lieu va
lang xa » lang ha, lang van
sach ty » sach y, sach tu, sach thu
nam tuc » nam thuc, nam truc, nam tu
va tinh » may tinh
tinh ve » trinh ve, tinh ven, dinh ve
cuu tre » cua tre, cau tren, cau treo
vu sach » vu bach, su sach, vu khach
tuc va » thuc va, truc va, tuc xa

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 ty ((lang xa) or (dang xay)) hoi. hieu van nam tuc va tinh ve ((cuu tre) or (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ty ((lang xa) OR (dang xay)) hoi. hieu van nam tuc va tinh ve ((cuu tre) OR (va triet)).
• Adding a wildcard symbol may retrieve word variants: vu sach ty ((lang xa) or (dang xay)) hoi. hieu van nam tuc va tinh ve ((cuu tre) or (va triet))*.