Perhaps you should try some spelling variations:
ngoc toan » ngoc tuan, ngoc tan, ngoc thanh
sanh doi » sach doi, thanh doi, tinh doi
cuu cong » cua cong, cac cong
khoa hoc » hoa hoc
nhan dan » phan dau, gian dan, nhan tai
so sanh » do sanh
doi tap » doi tac, doi dap, doi tai
va nhan » van nhan, ca nhan, va phan
hoc xa » hoc ma

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sanh doi tap, nghien ((cuu cong) OR (thu cong)) ngoc toan khoa hoc xa hoi va nhan dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh doi tap, nghien ((cuu cong) OR (thu cong)) ngoc toan khoa hoc xa hoi va nhan dan".
• Adding a wildcard symbol may retrieve word variants: so sanh doi tap, nghien ((cuu cong) OR (thu cong)) ngoc toan khoa hoc xa hoi va nhan dan*.