Perhaps you should try some spelling variations:
chat thuc » thuat thuc, nhan thuc, chat thai
hieu van » hieu va, thien van, hieu ve
thuc day » thuc dan, thuc vat
day danh » day manh, dai danh, dao danh
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
sai cua » dai cua, hai cua, bai cua
lai cua » dai cua, hai cua, lai chau

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 ty nang xa hoi. ((hieu van) or (lieu va)) chat thuc day danh ((sai cua) OR (lai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang xa hoi. ((hieu van) OR (lieu va)) chat thuc day danh ((sai cua) OR (lai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang xa hoi. ((hieu van) or (lieu va)) chat thuc day danh ((sai cua) OR (lai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang xa hoi. ((hieu van) or (lieu va)) chat thuc day danh ((sai cua) OR (lai cua)) tre*.