Perhaps you should try some spelling variations:
thien van » thi van
hanh vai » hanh vi, hanh va, hanh tai
hieu van » hieu va, lieu va
su sach » so sach, vu sach
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va
cua tre » cua te, cuu tre, cua triet
cac lo » cac lop, cac co, cac bo
lo va » lo van, lao va, ly va
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: su sach ky nang x hoi. ((hieu ve) or (((hieu van) OR (thien van)))) cac lo va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang x hoi. ((hieu ve) OR (((hieu van) OR (thien van)))) cac lo va hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang x hoi. ((hieu ve) or (((hieu van) OR (thien van)))) cac lo va hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. ((hieu ve) or (((hieu van) OR (thien van)))) cac lo va hanh vai cua tre*.