Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
sach ty » sach tu, sach thu, xach tay
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
nam xuc » cam xuc, nam xua, nam thuc
va hanh » van hanh, va thanh, va danh
ca viet » va viet, co viet, hoa viet
xuc va » duc va, tuc va, luc va
vi ca » vit ca, li ca, va ca

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach y) or (sach ty)) nang xa hoi. ((hieu van) OR (hieu va)) nam xuc va hanh vi ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach y) OR (sach ty)) nang xa hoi. ((hieu van) OR (hieu va)) nam xuc va hanh vi ca viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach y) or (sach ty)) nang xa hoi. ((hieu van) OR (hieu va)) nam xuc va hanh vi ca viet".
• Adding a wildcard symbol may retrieve word variants: su ((sach y) or (sach ty)) nang xa hoi. ((hieu van) OR (hieu va)) nam xuc va hanh vi ca viet*.