Perhaps you should try some spelling variations:
hanh lam » thanh lap, hanh kem, hanh va
hanh lai » hanh tai, thanh lap, thanh loi
te sach » toc sach
sach tu » sach thu, cach tu, sach ty
luc van » luoc van, luu van, duc van
cam luc » cam xuc, cau luc
cua tre » cua te, cuu tre, cua triet
tu nang » tru nang, tu nong, tu nano
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
o hai » co hai, so hai, o lai
o hoi » co hoi, o hoc, o hoa

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 tu nang ((o hoi) OR (o hai)). hieu ve cam luc van ((hanh lai) or (hanh lam)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach tu nang ((o hoi) OR (o hai)). hieu ve cam luc van ((hanh lai) OR (hanh lam)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach tu nang ((o hoi) OR (o hai)). hieu ve cam luc van ((hanh lai) or (hanh lam)) cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach tu nang ((o hoi) OR (o hai)). hieu ve cam luc van ((hanh lai) or (hanh lam)) cua tre*.