Perhaps you should try some spelling variations:
"dung sam doanh slippers" » "dung san doanh slippers", "dung nam danh slippers", "dung van doanh slippers", "dung lam doanh slippers", "dung sai doanh slippers", "dung sam doanh slippery", "dung sam doanh 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 sam doanh 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 sam doanh slippers") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung sam doanh slippers ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung sam doanh slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))*.