Perhaps you should try some spelling variations:
thuong con » thuong dong, truong cong, thong cong
cua thuong » cua truong, cua phuong, ca thuong
hanh tang » hanh trang, anh tang, hanh mang
lai toan » bai toan, lap toan, lai thanh
toan cao » toan ban, toan tap
bi tinh » vi tinh
con lai » cong lai, con lam, chong lai
so bi » so di, so li, so ki

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

• Performing a fuzzy search may retrieve terms with similar spellings: so bi tinh - ((hanh tang) or (canh tranh)) cua thuong con lai toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so bi tinh - ((hanh tang) OR (canh tranh)) cua thuong con lai toan cao.
• Adding a wildcard symbol may retrieve word variants: so bi tinh - ((hanh tang) or (canh tranh)) cua thuong con lai toan cao*.