Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
lang van » dang van, tang van, hoang van
doan van » doan va, hoang van, luan van
lam duoc » nam duoc, luat duoc, lam thuoc
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
van lam » van nam
lang xa » lang ha, dang xay
duoc ma » duoc lam
ma doan » ma dan, tap doan, va doanh
cua tre » cuu tre, cua triet, dua tren
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky ((lang xa) or (lang van)) hoi. hieu van lam duoc ma doan van ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky ((lang xa) OR (lang van)) hoi. hieu van lam duoc ma doan van ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky ((lang xa) or (lang van)) hoi. hieu van lam duoc ma doan van ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: toc sach ky ((lang xa) or (lang van)) hoi. hieu van lam duoc ma doan van ((cua tre) OR (cua te))*.