Perhaps you should try some spelling variations:
doanh khoa » toan khoa
van doanh » toan doanh, van dong, van thanh
sach moi » sach doi, sach hoi, bach mai
khoa hoc » hoa hoc
so sach » so sanh, bo sach, co sach
moi dap » hoi dap, doi dap, moi dan
cuu mot » cua mot, cuu mo, huu mot
mot van » mot vai, moi van, mot lan
hoa van » hoang van, hoa phan, hoa lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach moi dap, nghien cuu mot van doanh khoa hoc ma ((hoa van) OR (hoa dan)) pham van~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach moi dap, nghien cuu mot van doanh khoa hoc ma ((hoa van) OR (hoa dan)) pham van".
• Adding a wildcard symbol may retrieve word variants: so sach moi dap, nghien cuu mot van doanh khoa hoc ma ((hoa van) OR (hoa dan)) pham van*.