Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh tai » thanh tai, hang tai, han tai
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
cai hoi » cau hoi, dai hoi, lai hoi
cai hoa » cau hoa, cam hoa, dai hoa
van cam » van nam, van lam, van cau
cam luc » cam xuc, cau luc
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
luc va » duc va, tuc va, loc 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 ky nang ((cai hoi) OR (cai hoa)). hieu van cam luc va hanh tai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ((cai hoi) OR (cai hoa)). hieu van cam luc va hanh tai cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((cai hoi) OR (cai hoa)). hieu van cam luc va hanh tai cua tre*.