Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thu sach » thuat sach, thuoc sach, thu hoach
minh thi » dinh thi, minh thu, minh tri
tu sach » su sach, te sach, tu cach
thi cua » thai cua, thi cuc, tri cua
va minh » van minh, vua minh, va kinh
cao duc » dao duc, cao suc, giao duc
hieu ve » hieu va
cua te » cua tu
nang o » nang co, nang ho, nang ro
y nang » ky nang, ly nang, v nang
o hai » co hai, so hai, o lai

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) OR (thu sach)) y nang o hai. ((hieu ve) or (hieu van)) cao duc va minh thi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) y nang o hai. ((hieu ve) OR (hieu van)) cao duc va minh thi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) y nang o hai. ((hieu ve) or (hieu van)) cao duc va minh thi cua te".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) y nang o hai. ((hieu ve) or (hieu van)) cao duc va minh thi cua te*.