Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van chao » van chat, van hao, van cho
dinh dai » dinh dat, sinh dai, dinh dao
sach ky » sac ky, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
xu va » xu van, tu va, vu va
su va » su van, tu va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc ((sach ky) or (sach y)) nang xa hoi. hieu van chao ((xu va) OR (su va)) dinh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc ((sach ky) OR (sach y)) nang xa hoi. hieu van chao ((xu va) OR (su va)) dinh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc ((sach ky) or (sach y)) nang xa hoi. hieu van chao ((xu va) OR (su va)) dinh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: thuoc ((sach ky) or (sach y)) nang xa hoi. hieu van chao ((xu va) OR (su va)) dinh dai cua tre*.