Perhaps you should try some spelling variations:
trung thanh » truong thanh
khong thong » thong thong, khong trong, thong thuong
hieu lang » chieu sang, hieu quang, nhieu tang
trung cua » truong cua, trung tuan, trung cap
thong dan » thong van, tuong dan, thong den
doi hieu » doi chieu, doc hieu, doi hien
phan cac » nhan cach, phan lap, phan van
phan dau » phan tu, hang dau

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 thanh)) khong thong dan ((phan cac) OR (phan dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - thanh ((trung cua) OR (trung thanh)) khong thong dan ((phan cac) OR (phan dau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi hieu lang - thanh ((trung cua) or (trung thanh)) khong thong dan ((phan cac) OR (phan dau))".
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - thanh ((trung cua) or (trung thanh)) khong thong dan ((phan cac) OR (phan dau))*.