Perhaps you should try some spelling variations:
nghien huu » nghien cuu, nguyen huu, nhiem huu
cach hoc » cach thuc, cach thoi, dich hoc
tung hoc » trung hoc, tuong hoc, dung hoc
hoc hang » hoc hanh, hoc bang, hoc tang
hang hoa » hang khoa, thanh hoa, hang va
phan van » pham van, thanh van, luan van
su cach » su sach, tu cach, su cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: su cach hoc tap, nghien huu tung hoc hang hoa hoc ma ((hoa vo) or (hoa co)) phan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su cach hoc tap, nghien huu tung hoc hang hoa hoc ma ((hoa vo) OR (hoa co)) phan van.
• Adding a wildcard symbol may retrieve word variants: su cach hoc tap, nghien huu tung hoc hang hoa hoc ma ((hoa vo) or (hoa co)) phan van*.