Perhaps you should try some spelling variations:
thanh trang » thanh trung, hanh trang, thanh thang
hieu tinh » chieu tinh, lieu tinh, hieu binh
kieu tinh » lieu tinh, trieu tinh, diep tinh
dung cong » dung trong
khoan cam » khoa cam, phan cam, thuan cam
trang va » tran van, hang va
cong dan » cong san, cong tan, huong dan
khoan va » doan va, khoa ma, nhan va
va dung » van dung, va duong, vat dung

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) or (kieu tinh)) - thanh trang va dung cong dan ((khoan cam) OR (khoan va))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu tinh) OR (kieu tinh)) - thanh trang va dung cong dan ((khoan cam) OR (khoan va)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu tinh) or (kieu tinh)) - thanh trang va dung cong dan ((khoan cam) OR (khoan va))".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu tinh) or (kieu tinh)) - thanh trang va dung cong dan ((khoan cam) OR (khoan va))*.