Perhaps you should try some spelling variations:
"dung vien dat slippers" » "duong vien dat slippers", "dung viet dat slippers", "dung tien dat slippers", "dung vien dai slippers", "dung vien da slippers", "dung viec dat slippers", "dung vien dat slippery", "dung vien dat 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: (((("dung vien dat 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 vien dat slippers") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung vien dat slippers ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung vien dat slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))*.