Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
thuat mach » thuat sach, thuat tach, thuyet mach
trinh quan » tinh quang, trinh luat, trinh han
quan trong » gian trong
thuat tac » thuat tach, thuat tao, thuat tai
cong vang » cong lang, cong quang, cong ngang
cong van » cong san, song van, cong tan

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((thuat mach) or (thuat tac)) - hanh trinh quan trong ((cong van) OR (cong vang)) van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((thuat mach) OR (thuat tac)) - hanh trinh quan trong ((cong van) OR (cong vang)) van ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((thuat mach) or (thuat tac)) - hanh trinh quan trong ((cong van) OR (cong vang)) van ban".
• Adding a wildcard symbol may retrieve word variants: ho ((thuat mach) or (thuat tac)) - hanh trinh quan trong ((cong van) OR (cong vang)) van ban*.