Perhaps you should try some spelling variations:
hieu cua » hieu qua, dieu cua, bieu cua
van tuan » van quan, van ban, anh tuan
va triet » va thiet, va trien, ve triet
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
cac luc » cau luc, coc luc, cac nuoc
luc van » luoc van, luu van, duc van
tuan ke » tuan le, toan ke, tuan kiet
ke va » te va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky ((nang xa) or (nang ma)) hoi. hieu cua cac luc van tuan ke va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((nang xa) OR (nang ma)) hoi. hieu cua cac luc van tuan ke va triet.
• Adding a wildcard symbol may retrieve word variants: te sach ky ((nang xa) or (nang ma)) hoi. hieu cua cac luc van tuan ke va triet*.