Perhaps you should try some spelling variations:
nganh hoa » thanh hoa, khanh hoa, danh hoa
mach hoc » cach hoc, dich hoc, anh hoc
cong hoc » dong hoc, cong coc, cong ho
cong hoa » dong hoa, dong hoc, hang hoa
phan dan » phan dang, phan dau, nhan dan
tu mach » tu cach, tu manh, tu hach
va phan » van phan, va phat, va phap
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu mach hoc tap, nghien cuu ((cong hoc) OR (cong hoa)) nganh hoa hoc ma hoi va phan dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu mach hoc tap, nghien cuu ((cong hoc) OR (cong hoa)) nganh hoa hoc ma hoi va phan dan".
• Adding a wildcard symbol may retrieve word variants: tu mach hoc tap, nghien cuu ((cong hoc) OR (cong hoa)) nganh hoa hoc ma hoi va phan dan*.