Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
hieu van » hieu va, thien van, lieu va
lang xa » lang ha, dang xay, lang van
sach ty » sach y, sach tu, xach tay
ca dan » cac dan, ca dao
va cua » va chua, via cua, ca cua
van am » van nam, van lam, van dam
va dan » va dao, va dau, va dap
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 ty) or (sach thu)) lang xa hoi. hieu van am thuc ((va dan) OR (ca dan)) va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ty) OR (sach thu)) lang xa hoi. hieu van am thuc ((va dan) OR (ca dan)) va cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ty) or (sach thu)) lang xa hoi. hieu van am thuc ((va dan) OR (ca dan)) va cua te".
• Adding a wildcard symbol may retrieve word variants: toc ((sach ty) or (sach thu)) lang xa hoi. hieu van am thuc ((va dan) OR (ca dan)) va cua te*.