Perhaps you should try some spelling variations:
thuat sac » thuat sach, thuat san, thuat tac
hieu van » hieu va, thien van, lieu va
tan anh » tuan anh, tran anh, toan anh
cao duc » dao duc, cao suc, giao duc
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, me hoi
anh vi » hanh vi, anh va, anh ve
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sac ky nang ((ma hoi) or (ma hoa)). hieu van ((cao duc) or (cao su)) tan anh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sac ky nang ((ma hoi) OR (ma hoa)). hieu van ((cao duc) OR (cao su)) tan anh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: thuat sac ky nang ((ma hoi) or (ma hoa)). hieu van ((cao duc) or (cao su)) tan anh vi cua tre*.