Perhaps you should try some spelling variations:
vanh dai » van dai, vanh tai, lanh dao
vu sach » vu bach, su sach, vu khach
hieu va » lieu va, hieu qua
va cham » va chat, va tham
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
cua tre » cua te, cuu tre, cua triet
luc va » duc va, loc va
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 y ((nang xa) or (nang ma)) hoi. hieu va cham ((luc va) OR (tuc va)) vanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y ((nang xa) OR (nang ma)) hoi. hieu va cham ((luc va) OR (tuc va)) vanh dai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach y ((nang xa) or (nang ma)) hoi. hieu va cham ((luc va) OR (tuc va)) vanh dai cua tre*".