Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach ky » sac ky, sach y, sach ty
van anh » van thanh, tuan anh, van minh
duc van » duc va, duc tan, duc manh
hieu va » lieu va, hieu qua
hieu ve » hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
anh le » manh le, oanh le, anh ve
cua tu » cua tuc, cua su, cua cu

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 hoi. ((hieu ve) or (hieu va)) pham duc van anh le ((cua te) OR (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky lang xa hoi. ((hieu ve) OR (hieu va)) pham duc van anh le ((cua te) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky lang xa hoi. ((hieu ve) or (hieu va)) pham duc van anh le ((cua te) OR (cua tu))".
• Adding a wildcard symbol may retrieve word variants: toc sach ky lang xa hoi. ((hieu ve) or (hieu va)) pham duc van anh le ((cua te) OR (cua tu))*.