Perhaps you should try some spelling variations:
"dung java java snippets" » "dung va java snippets"
"cong tan tran slippers" » "cong tac tran slippers", "cong san tran slippers", "cong thanh tran slippers", "cong tan tran slippery", "cong tan tran grippers"
"locating bug code snippets" » "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: (((("cong tan tran slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("cong tan tran slippers") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( cong tan tran slippers ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("cong tan tran slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))*.