Perhaps you should try some spelling variations:
chat thuc » thuat thuc, nhan thuc, chat thai
van chat » cao chat
dai danh » dai dang, dao danh, loai danh
day danh » day manh, dao danh, day dan
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
ty nang » ky nang, ty hang, ly nang
cua tre » cua te, cuu tre, cua triet

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