Perhaps you should try some spelling variations:
hieu luan » hieu luat, hieu quan, tieu luan
luan chat » luan chi, van chat, luan phan
dai khoa » da khoa, tai khoa, dai hoa
chat huu » pham huu
dac khoa » da khoa, dau khoa, cac khoan
dau hoa » dau khoa, cau hoa, dai hoa
te sach » toc sach
cam dan » cac dan, ca dan, nam dan
huu cam » huu lam, huu tam, huu chau
cao hoa » cao hoat, cao khoa, cau hoa
y nang » ky nang, ly nang, v nang

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 y nang cao hoa. hieu luan chat huu cam dan ((dau hoa) or (((dac khoa) OR (dai khoa)))) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang cao hoa. hieu luan chat huu cam dan ((dau hoa) OR (((dac khoa) OR (dai khoa)))) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang cao hoa. hieu luan chat huu cam dan ((dau hoa) or (((dac khoa) OR (dai khoa)))) viet".
• Adding a wildcard symbol may retrieve word variants: te sach y nang cao hoa. hieu luan chat huu cam dan ((dau hoa) or (((dac khoa) OR (dai khoa)))) viet*.