Perhaps you should try some spelling variations:
thuat sac » thuat sach, thuat san, thuat tac
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
van hac » van hoc, van ha, van hai
hac dat » hoc dat, tac dat, hoach dat
dat van » dao van, dat va, dam van
sac ky » cac ky, sai ky
ma hoi » mai hoi, ma hoa, me hoi
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 (xa hoi)). hieu van hac dat van hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sac ky nang ((ma hoi) OR (xa hoi)). hieu van hac dat van hanh vi cua vat.
• Adding a wildcard symbol may retrieve word variants: thuat sac ky nang ((ma hoi) or (xa hoi)). hieu van hac dat van hanh vi cua vat*.