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