Perhaps you should try some spelling variations:
"cong trinh quan van thu dung cua ban" » "cong tinh quang van thu dung cua ban", "cong trinh han van thu dung cua ban", "cong trinh luan van thu dung cua ban", "cong trinh quan va thu dung cua ban", "cong trinh quan luan thu dung cua ban", "cong trinh quan van thuy dung cua ban", "cong trinh quan van thuc dung cua ban", "cong trinh quan van thu dang cua ban", "cong trinh quan van thu dung luan ban", "cong trinh quan van thu dung cho ban"
"cong trinh luat van thu dung cua ban" » "cong trinh luat van thuy dung cua ban", "cong trinh luat van thuc dung cua ban", "cong trinh luat van thu dang cua ban", "cong trinh luat van thu dung luan ban", "cong trinh luat van thu dung cho ban", "cong trinh luan van thu dung cua ban", "cong trinh luat dan thu dung cua ban", "cong trinh luat va thu dung cua ban"

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("cong trinh quan van thu dung cua ban") OR ("cong trinh luat van thu dung cua ban"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"cong trinh quan van thu dung cua ban\") OR (\"cong trinh luat van thu dung cua ban\"))".
• Removing quotes may allow a broader search: (( cong trinh quan van thu dung cua ban ) OR ( cong trinh luat van thu dung cua ban )).
• Adding a wildcard symbol may retrieve word variants: (("cong trinh quan van thu dung cua ban") OR ("cong trinh luat van thu dung cua ban"))*.