Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
thanh ha » thanh hoa, thanh hai, nhanh ha
nam thuc » nam thuoc, am thuc, nam tu
su sach » so sach, vu sach
nang ma » sang ma, nang cao, mang may
tang ma » mang may, tang van
sach v » sach va, sach y, sach 2
ha cua » hoa cua, hai cua, nha cua
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: su sach v ((nang ma) OR (tang ma)) hoi. hieu van ((nam thuc) or (nam thu)) ban thanh ha cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach v ((nang ma) OR (tang ma)) hoi. hieu van ((nam thuc) OR (nam thu)) ban thanh ha cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach v ((nang ma) OR (tang ma)) hoi. hieu van ((nam thuc) or (nam thu)) ban thanh ha cua te".
• Adding a wildcard symbol may retrieve word variants: su sach v ((nang ma) OR (tang ma)) hoi. hieu van ((nam thuc) or (nam thu)) ban thanh ha cua te*.