Perhaps you should try some spelling variations:
"vu canh tranh tren" » "vu canh trinh tren", "vu canh tran tren", "vu canh tranh trong", "ve canh tranh tren", "vu anh tranh tren", "vu manh tranh tren"
"vu hoach dinh tren" » "vu hoang dinh tren", "vu hoach dinh trong", "vu hoach dinh tri", "vu hoach dinh tieu", "quy hoach dinh tren", "thu hoach dinh tren", "qui hoach dinh tren"
"vu hoach dinh dien" » "vu hoang dinh dien", "vu hoach tinh dien", "vu hoach kinh dien", "vu hoach dich dien", "quy hoach dinh dien", "thu hoach dinh dien", "qui hoach dinh dien"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("vu canh tranh tren") or ((("vu hoach dinh tren") OR ("vu hoach dinh dien"))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("vu canh tranh tren") OR ((("vu hoach dinh tren") OR ("vu hoach dinh dien")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"vu canh tranh tren\") or (((\"vu hoach dinh tren\") OR (\"vu hoach dinh dien\"))))".
• Removing quotes may allow a broader search: (( vu canh tranh tren ) or ((( vu hoach dinh tren ) OR ( vu hoach dinh dien )))).
• Adding a wildcard symbol may retrieve word variants: (("vu canh tranh tren") or ((("vu hoach dinh tren") OR ("vu hoach dinh dien"))))*.