Perhaps you should try some spelling variations:
hinh bai » hinh tai, hinh thai, tinh bac
sach ky » sach y, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va nhan » van nhan, ca nhan, va phan
bai cua » ban cua, dai cua, bai ca
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
luc va » tuc va, loc 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 (sac ky)) nang xa hoi. hieu va nhan ((luc va) or (duc va)) hinh bai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc ((sach ky) OR (sac ky)) nang xa hoi. hieu va nhan ((luc va) OR (duc va)) hinh bai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc ((sach ky) OR (sac ky)) nang xa hoi. hieu va nhan ((luc va) or (duc va)) hinh bai cua tre".
• Adding a wildcard symbol may retrieve word variants: thuoc ((sach ky) OR (sac ky)) nang xa hoi. hieu va nhan ((luc va) or (duc va)) hinh bai cua tre*.