Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
lang ha » long ha
hieu ve » hieu va, hieu van
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
xuc va » tuc va, luc va, xac va

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

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