Perhaps you should try some spelling variations:
thanh toan » thanh hoa, thanh san, tinh toan
dan thanh » dang thanh, danh thanh, ban thanh
sach hoi » sach doi, sach moi, cach thoi
khoa hoc » hoa hoc
tu sach » thu sach, su sach, te sach
hoi tap » hoi dap, hoi tai, hai tap
cuu mon » cuu mo, cuu mot, cuu cong
hoc tan » hoc tang, hoc dan, hoc tai
hoi dan » hoa dan, hoc dan, hoi dap
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: tu sach hoi tap, nghien cuu mon ((hoc tan) OR (hoc tap)) khoa hoc xa hoi dan thanh toan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach hoi tap, nghien cuu mon ((hoc tan) OR (hoc tap)) khoa hoc xa hoi dan thanh toan".
• Adding a wildcard symbol may retrieve word variants: tu sach hoi tap, nghien cuu mon ((hoc tan) OR (hoc tap)) khoa hoc xa hoi dan thanh toan*.