Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
song ly » dong ly, hong ly, huong ly
truc va » thuc vat, trung va
vai cua » dai cua, hai cua, lai cua
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
ly nang » ky nang, ly hang, ly vang
hieu ve » hieu va, hieu van
ve cau » ke cau, va cau, ve cac
o hai » co hai, so hai, o lai
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat song ly nang ((x hoi) or (o hai)). hieu ve cau ((truc va) OR (thuc va)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat song ly nang ((x hoi) OR (o hai)). hieu ve cau ((truc va) OR (thuc va)) hanh vai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat song ly nang ((x hoi) or (o hai)). hieu ve cau ((truc va) OR (thuc va)) hanh vai cua tre*".