Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hieu van » thien van, lieu va, hieu ve
cua viet » ca viet, hoa viet, cua vat
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
y nang » ky nang, ly nang, v nang
xuc va » duc va, tuc va, luc va
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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 (su sach)) y nang x hoi. ((hieu van) or (hieu va)) cam xuc va hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuat sach) OR (su sach)) y nang x hoi. ((hieu van) OR (hieu va)) cam xuc va hanh vi cua viet.
• Adding a wildcard symbol may retrieve word variants: ((thuat sach) or (su sach)) y nang x hoi. ((hieu van) or (hieu va)) cam xuc va hanh vi cua viet*.