Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
cau treo » cau theo, cau tren, cau triet
thanh di » thanh doi, thanh de, thanh do
cuu tre » cua tre, cau tren
tuc van » thuc van, truc van, tuc va
su sach » so sach, vu sach
ty nang » ky nang, ty hang, ly nang
dau tuc » dau tu, dao tuc, cau truc
va dau » va dao

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 ((ty nang) or (ty xang)) xa hoi. lieu va dau tuc van thanh di ((cuu tre) OR (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ty nang) OR (ty xang)) xa hoi. lieu va dau tuc van thanh di ((cuu tre) OR (cau treo)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ty nang) or (ty xang)) xa hoi. lieu va dau tuc van thanh di ((cuu tre) OR (cau treo))".
• Adding a wildcard symbol may retrieve word variants: su sach ((ty nang) or (ty xang)) xa hoi. lieu va dau tuc van thanh di ((cuu tre) OR (cau treo))*.