Perhaps you should try some spelling variations:
phuong tinh » phuong trinh, phuong binh, phuong linh
khuong tinh » chuong trinh, phuong trinh, phuong binh
trung tuan » trung thanh, trung tam, tran tuan
hieu lang » chieu sang, hieu quang, nhieu tang
trung cua » truong cua, trung cap, dung cua
doi hieu » doi chieu, doc hieu, doi hien
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: doi hieu lang - thanh ((trung cua) OR (trung tuan)) nhua ((phuong tinh) or (khuong tinh)) toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - thanh ((trung cua) OR (trung tuan)) nhua ((phuong tinh) OR (khuong tinh)) toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi hieu lang - thanh ((trung cua) OR (trung tuan)) nhua ((phuong tinh) or (khuong tinh)) toan tap".
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - thanh ((trung cua) OR (trung tuan)) nhua ((phuong tinh) or (khuong tinh)) toan tap*.