Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
nhung cong » thong cong, hang cong, nhung don
lang thanh » dang thanh, tang thanh, lang thang
dong thanh » truong thanh
hien hanh » dieu hanh
trinh van » trinh han, trinh quan, trinh toan
dung cong » dung trong

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

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