Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
hieu tinh » chieu tinh, lieu tinh, kieu tinh
doc hieu » toc thieu, hoc thieu, hoc hien
tinh cua » trinh cua, tinh chat, tranh cua
sinh cua » manh cua, dinh cuu, sinh va
cong dan » cong san, cong tan, huong dan
toan tap » toan ban
toan cao » 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: doc hieu tinh - nhanh ((tinh cua) OR (sinh cua)) thong cong dan ((toan tap) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu tinh - nhanh ((tinh cua) OR (sinh cua)) thong cong dan ((toan tap) OR (toan cao)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu tinh - nhanh ((tinh cua) OR (sinh cua)) thong cong dan ((toan tap) or (toan cao))".
• Adding a wildcard symbol may retrieve word variants: doc hieu tinh - nhanh ((tinh cua) OR (sinh cua)) thong cong dan ((toan tap) or (toan cao))*.