Perhaps you should try some spelling variations:
"dung java java snippets" » "dung va java snippets"
"dung cao sach slippers" » "duong cao sach slippers", "dung cho sach slippers", "dung co sach slippers", "dung ao sach slippers", "dung cau sach slippers", "dung cao sach slippery", "dung cao sach 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: (((("dung cao sach slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung cao sach slippers") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung cao sach slippers ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung cao sach slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))*.