Perhaps you should try some spelling variations:
doanh khoa » toan khoa
hoc doanh » hoa doanh, hoc danh, hoc dan
thu sach » tu sach, thuat sach, thuoc sach
sach hoi » sach doi, sach moi, cach thoi
hoc mai » hoc dai, hoc bai, hoc may
hoi van » hoi va, hoi dan, hai van
van can » van canh, van ban, ban can
can ban » van ban, toan ban
mo hoc » mon hoc, co hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach hoi dap, nghien cuu mo hoc doanh khoa ((hoc mai) OR (hoc ma)) hoi van can ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach hoi dap, nghien cuu mo hoc doanh khoa ((hoc mai) OR (hoc ma)) hoi van can ban".
• Adding a wildcard symbol may retrieve word variants: thu sach hoi dap, nghien cuu mo hoc doanh khoa ((hoc mai) OR (hoc ma)) hoi van can ban*.