Perhaps you should try some spelling variations:
trinh toan » tinh toan, thanh toan, trinh han
thong cong » trong cong, tong cong, thong thong
hoc thieu » toc thieu, hoc hien
ho chieu » theo chieu, doi chieu, mot chieu
trinh ve » trinh he, trinh va, trinh vi
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan tap » toan ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) OR (hoc thieu)) xanh - canh ((trinh ve) or (trinh toan)) thong cong dan toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (hoc thieu)) xanh - canh ((trinh ve) OR (trinh toan)) thong cong dan toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (hoc thieu)) xanh - canh ((trinh ve) or (trinh toan)) thong cong dan toan tap".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (hoc thieu)) xanh - canh ((trinh ve) or (trinh toan)) thong cong dan toan tap*.