Perhaps you should try some spelling variations:
nghien cac » nghiep cach, nghien cuu, nghiep cay
manh hon » manh ho, minh hon, manh huong
cac cong » cua cong
cong hoc » dong hoc, cong hoa, cong coc
dan cung » dan dung, dan vung, dan ung
ban cung » ban cong, bai cung, ban dung
tu manh » tu minh, tu hanh, vu manh
hon tap » hoc tap, han tap, con tap
hoc mai » hoc ma, hoc dai, hoc bai
mai hoi » mai khoi, dai hoi, lai hoi
va luan » vay luan, van luan, va quan

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu manh hon tap, nghien cac cong hoc ((dan cung) or (ban cung)) hoc mai hoi va luan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu manh hon tap, nghien cac cong hoc ((dan cung) OR (ban cung)) hoc mai hoi va luan van.
• Adding a wildcard symbol may retrieve word variants: tu manh hon tap, nghien cac cong hoc ((dan cung) or (ban cung)) hoc mai hoi va luan van*.