Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
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
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
su sach » so sach, vu sach
sach v » sach va, sach y, sach 2
ha cua » hoa cua, hai cua, nha cua

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 (sang ma)) hoi. hieu van ((nam thuc) or (nam thu)) ban thanh ha cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach v ((nang ma) OR (sang ma)) hoi. hieu van ((nam thuc) OR (nam thu)) ban thanh ha cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach v ((nang ma) OR (sang ma)) hoi. hieu van ((nam thuc) or (nam thu)) ban thanh ha cua triet".
• Adding a wildcard symbol may retrieve word variants: su sach v ((nang ma) OR (sang ma)) hoi. hieu van ((nam thuc) or (nam thu)) ban thanh ha cua triet*.