Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
mach hoc » cach hoc, dich hoc, anh hoc
cuu cong » cua cong, thu cong, cac cong
cong hoc » dong hoc, cong hoa, cong coc
hoc toan » hoc tan, hop toan, hoa toan
khoa hoc » hoa hoc
van nhan » van phan, danh nhan, van khanh
te mach » ke mach, te sach, tim mach
hoc dai » hoc dan
dai hoi » dai hoc, dai hai, dai moi

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

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