Perhaps you should try some spelling variations:
hieu luan » hieu luat, hieu quan, tieu luan
luan phan » luan van, luan hoan
su triet » su viet, su tien, ve triet
phan duc » pham duc, phan tu, phan dau
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
tu sach » thu sach, su sach, te sach
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
mang xa » lang xa, mang may, dang xay
vi su » va su, ve su, ki su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y ((mang xa) or (((nang ma) OR (sang ma)))) hoi. hieu luan phan duc va danh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((mang xa) OR (((nang ma) OR (sang ma)))) hoi. hieu luan phan duc va danh vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((mang xa) or (((nang ma) OR (sang ma)))) hoi. hieu luan phan duc va danh vi su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach y ((mang xa) or (((nang ma) OR (sang ma)))) hoi. hieu luan phan duc va danh vi su triet*.