Perhaps you should try some spelling variations:
"nhung thoi xuan van. biet the hieu luc xuc" » "nhung thi xuan van. biet the hieu luc xuc", "phung thi xuan van. biet the hieu luc xuc", "nhung loi xuan van. biet the hieu luc xuc", "nhung tho xuan van. biet the hieu luc xuc", "nhung thoi xua van. biet the hieu luc xuc", "nhung thoi quan van. biet the hieu luc xuc", "nhung thoi xuan can. biet the hieu luc xuc", "nhung thoi xuan tan. biet the hieu luc xuc", "nhung thoi xuan van. biet the hieu luat xuc", "nhung thoi xuan van. biet the hieu qua xuc"
"nhung luc luan van. biet the hien gian xu" » "nhung lua luan van. biet the hien gian xu", "nhung cuoc luan van. biet the hien gian xu", "nhung khuc luan van. biet the hien gian xu", "nhung luc luan van. biet the hien giam xu", "nhung luc luan van. biet the thien giap xu", "nhung luc luan van. biet the kien giang xu", "nhung ly luan van. biet the hien gian xu", "nhung tu luan van. biet the hien gian xu"

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: (("nhung thoi xuan van. biet the hieu luc xuc") or ("nhung luc luan van. biet the hien gian xu"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("nhung thoi xuan van. biet the hieu luc xuc") OR ("nhung luc luan van. biet the hien gian xu")).
• Removing quotes may allow a broader search: (( nhung thoi xuan van. biet the hieu luc xuc ) or ( nhung luc luan van. biet the hien gian xu )).
• Adding a wildcard symbol may retrieve word variants: (("nhung thoi xuan van. biet the hieu luc xuc") or ("nhung luc luan van. biet the hien gian xu"))*.