Perhaps you should try some spelling variations:
trinh cua » tinh cua, trinh quan, trinh luan
tong cong » trong cong, cong cong, dung cong
hoc chat » hoc cao, hoc phan, hoc cua
hoc phat » hoc phan, hoc pho
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc chat) or (hoc phat)) tinh - hanh ((trinh cua) OR (trinh luat)) tong cong dan toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc chat) OR (hoc phat)) tinh - hanh ((trinh cua) OR (trinh luat)) tong cong dan toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc chat) or (hoc phat)) tinh - hanh ((trinh cua) OR (trinh luat)) tong cong dan toan ban".
• Adding a wildcard symbol may retrieve word variants: ((hoc chat) or (hoc phat)) tinh - hanh ((trinh cua) OR (trinh luat)) tong cong dan toan ban*.