Perhaps you should try some spelling variations:
nghien cac » nghiep cach, nghien cuu, nghiep cay
nganh khoa » nganh hoa, nganh khong, doanh khoa
hoc nganh » hoc nhanh
mach hoc » cach hoc, dich hoc, anh hoc
cac cong » cua cong
cong hoc » dong hoc, cong hoa, cong coc
khoa hoc » hoa hoc
mai hoi » mai khoi, lai hoi, mai doi
dai hoi » dai hoc, dai hai, dai moi
va luan » vay luan, van luan, va quan
tim » time

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

• Performing a fuzzy search may retrieve terms with similar spellings: tim mach hoc tap, nghien cac cong hoc nganh khoa hoc ((mai hoi) OR (dai hoi)) va luan van~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tim mach hoc tap, nghien cac cong hoc nganh khoa hoc ((mai hoi) OR (dai hoi)) va luan van".
• Adding a wildcard symbol may retrieve word variants: tim mach hoc tap, nghien cac cong hoc nganh khoa hoc ((mai hoi) OR (dai hoi)) va luan van*.