Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thanh dam » thanh dat, thanh nam, thanh tam
sach phu » sach thu, sach phat, sach thue
phu lang » phap lang, phu khang, phu luong
hieu van » thien van, lieu va, hieu ve
tu sach » thu sach, su sach, te sach
cuu tre » cua tre, cau tren, cau treo
cam tuc » cam xuc, cam tu, nam thuc
tuc van » thuc van, truc van, tuc va
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
su tien » su kien, su hien, tu tieng

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 phu lang xa hoi. ((hieu van) OR (hieu va)) cam tuc van thanh dam ((cuu tre) or (su tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach phu lang xa hoi. ((hieu van) OR (hieu va)) cam tuc van thanh dam ((cuu tre) OR (su tien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach phu lang xa hoi. ((hieu van) OR (hieu va)) cam tuc van thanh dam ((cuu tre) or (su tien))".
• Adding a wildcard symbol may retrieve word variants: tu sach phu lang xa hoi. ((hieu van) OR (hieu va)) cam tuc van thanh dam ((cuu tre) or (su tien))*.