Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
sach kha » sach nha, sach ha, sach tham
kha nang » phap nang, ky nang, ki nang
hanh vai » hanh vi, hanh tai, hanh van
hanh va » hang va, hanh vi
thuc va » thuc vat, thuc dan, thuc day
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach kha nang o hoi. hieu ve cam thuc va ((hanh vai) or (hanh va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach kha nang o hoi. hieu ve cam thuc va ((hanh vai) OR (hanh va)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach kha nang o hoi. hieu ve cam thuc va ((hanh vai) or (hanh va)) cua tre*.