Perhaps you should try some spelling variations:
"cuong luan van snippets" » "cuong quan van snippets", "cong luan van snippets", "truong luan van snippets", "cuong luan van slippers"
"dung java java snippets" » "dung va java snippets", "dung java java slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

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: (((("cuong luan van snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("cuong luan van snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( cuong luan van snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("cuong luan van snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.