Perhaps you should try some spelling variations:
doanh khoa » toan khoa
ban thanh » ban hanh, ban hang
cuu cong » cua cong, thu cong, cac cong
so doanh » so danh, su doanh, hoa doanh
khoa hoc » hoa hoc
thai ban » thai bang, tai ban, thai van
cong so » cong san, cong hoa
ma thai » mai thai, mau thai, ca thai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cach) OR (tu cac)) hoc tap, nghien cuu cong so doanh khoa hoc ma thai ban thanh pho~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) OR (tu cac)) hoc tap, nghien cuu cong so doanh khoa hoc ma thai ban thanh pho".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) OR (tu cac)) hoc tap, nghien cuu cong so doanh khoa hoc ma thai ban thanh pho*.