Perhaps you should try some spelling variations:
thuat sach » thuat lanh
thuat san » thuat toan, thuat song, thuat lanh
van hanh » van thanh, ban hanh, van anh
mai hoi » mai khoi, dai hoi, lai hoi
hac dat » hoc dat, tac dat, hoach dat
dat van » dao van, dat va, dam van
va hac » van hac, va khac, va cac
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 sach) OR (thuat san)) ky nang ((mai hoi) or (xa hoi)). lieu va hac dat van hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuat sach) OR (thuat san)) ky nang ((mai hoi) OR (xa hoi)). lieu va hac dat van hanh vi cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuat sach) OR (thuat san)) ky nang ((mai hoi) or (xa hoi)). lieu va hac dat van hanh vi cua vat".
• Adding a wildcard symbol may retrieve word variants: ((thuat sach) OR (thuat san)) ky nang ((mai hoi) or (xa hoi)). lieu va hac dat van hanh vi cua vat*.