Perhaps you should try some spelling variations:
thien thanh » tien thanh, thi thanh, hien hanh
dung thuong » dung trong, hang thuong, dung thuoc
cong thuong » hang thuong
thien dang » thien bang, thien danh, thien nang
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
tinh cua » trinh cua, sinh cua, tinh chat
van phan » van phong, van thanh, luan phan
phan lap » phan dau

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thien thanh) or (thien dang)) - hanh tinh cua ((dung thuong) OR (cong thuong)) van phan lap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thien thanh) OR (thien dang)) - hanh tinh cua ((dung thuong) OR (cong thuong)) van phan lap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thien thanh) or (thien dang)) - hanh tinh cua ((dung thuong) OR (cong thuong)) van phan lap".
• Adding a wildcard symbol may retrieve word variants: hoc ((thien thanh) or (thien dang)) - hanh tinh cua ((dung thuong) OR (cong thuong)) van phan lap*.