Perhaps you should try some spelling variations:
thien van » thi van
hieu van » hieu va, lieu va, hieu ve
van dinh » van minh, van dich, va dinh
chua tre » chua tri, cua tre, chua trieu
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
va tinh » may tinh
va chua » vua chua, ca chua, va chu
y nang » ky nang, ly nang, v nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y nang xa hoi. ((hieu van) OR (thien van)) chao xu ((va tinh) or (van dinh)) va chua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. ((hieu van) OR (thien van)) chao xu ((va tinh) OR (van dinh)) va chua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang xa hoi. ((hieu van) OR (thien van)) chao xu ((va tinh) or (van dinh)) va chua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. ((hieu van) OR (thien van)) chao xu ((va tinh) or (van dinh)) va chua tre*.