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