Perhaps you should try some spelling variations:
thuat sach » thuat san
thuat lanh » thuat lap, thuat san
van hanh » van thanh, ban hanh, van anh
nang ma » tang ma, sang ma, nang cao
van hac » van hoc, van hai, van chat
dat van » dao van, dat va, dam van
ma hoi » mai hoi, xa hoi, ma hoa
van ha » van hoa, van chat, van phan
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 lanh)) ky nang ma hoi. hieu ((van hac) or (van ha)) dat van hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuat sach) OR (thuat lanh)) ky nang ma hoi. hieu ((van hac) OR (van ha)) dat van hanh vi cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuat sach) OR (thuat lanh)) ky nang ma hoi. hieu ((van hac) or (van ha)) dat van hanh vi cua vat".
• Adding a wildcard symbol may retrieve word variants: ((thuat sach) OR (thuat lanh)) ky nang ma hoi. hieu ((van hac) or (van ha)) dat van hanh vi cua vat*.