Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
van dinh » van minh, van dich, va dinh
duc van » duc va, duc tan, duc manh
hieu va » lieu va, hieu qua
hieu ve » hieu van
nang xa » nang x, lang xa, nang ma
sach 2 » sach y
2 nang » v nang
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach 2 nang xa hoi. ((hieu ve) OR (hieu va)) pham duc van dinh ((vi cua) OR (di cua)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach 2 nang xa hoi. ((hieu ve) OR (hieu va)) pham duc van dinh ((vi cua) or (di cua)) tre~".
• Adding a wildcard symbol may retrieve word variants: thuat sach 2 nang xa hoi. ((hieu ve) OR (hieu va)) pham duc van dinh ((vi cua) or (di cua)) tre*.