Perhaps you should try some spelling variations:
nghien huu » nghien cuu, nguyen huu, nhiem huu
tran khoa » toan khoa, san khoa, nhan khoa
thu sach » thuat sach, thuoc sach, thu hoach
hoa tran » hoa trang, hoan tran, hoa tan
khoa hoc » hoa hoc
dap luan » dan luan, dap luat, dat luan
tu sach » su sach, te sach, tu cach
huu mon » huu son, hau mon, huu mot
mon hoa » mon hoc, dong hoa, cong hoa
hoc xa » hoc ma

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) or (thu sach)) hoc tap, nghien huu mon hoa tran khoa hoc xa hoi dap luan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) hoc tap, nghien huu mon hoa tran khoa hoc xa hoi dap luan van.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) hoc tap, nghien huu mon hoa tran khoa hoc xa hoi dap luan van*.