Perhaps you should try some spelling variations:
dung thanh » duong thanh, dong thanh, dang thanh
thanh vai » thanh hai, thanh van, thanh tai
ve triet » va trien, su triet
nam thuc » nam thuoc, am thuc, nam tu
sach ky » sac ky, sach y, sach ty
su sach » so sach, vu sach
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
vai ve » va ve, dai ve, vai va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky ((nang xa) or (nang ma)) hoi. hieu va ((nam thuc) OR (nam thu)) dung thanh vai ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang xa) OR (nang ma)) hoi. hieu va ((nam thuc) OR (nam thu)) dung thanh vai ve triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((nang xa) or (nang ma)) hoi. hieu va ((nam thuc) OR (nam thu)) dung thanh vai ve triet*".