Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
thanh toan » thanh hoa, thanh san, tinh toan
hieu lang » chieu sang, hieu quang, nhieu tang
trinh cua » tinh cua, trinh luat, trinh quan
trinh han » trinh quan
hach toan » manh toan
hoi hieu » hoi phieu, hoi tieu, moi hieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoi hieu lang - hanh ((trinh cua) or (trinh han)) thong cong ((hach toan) OR (thanh toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi hieu lang - hanh ((trinh cua) OR (trinh han)) thong cong ((hach toan) OR (thanh toan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoi hieu lang - hanh ((trinh cua) or (trinh han)) thong cong ((hach toan) OR (thanh toan)) cao".
• Adding a wildcard symbol may retrieve word variants: hoi hieu lang - hanh ((trinh cua) or (trinh han)) thong cong ((hach toan) OR (thanh toan)) cao*.