Perhaps you should try some spelling variations:
hanh trang » thanh trung, canh tranh, hanh trinh
hieu tinh » chieu tinh, lieu tinh, hieu binh
kieu tinh » lieu tinh, trieu tinh, diep tinh
hang cong » dang cong, hang nong, thanh cong
bang cong » dang cong, bang song, dung cong
trang va » tran van, hang va
tan phan » toan phan, than phan, van phan

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