Perhaps you should try some spelling variations:
"tran viet trong slippers" » "tran viet trung slippers", "tran viet thong slippers", "tran viet huong slippers", "trien viet trong slippers", "gian viet trong slippers", "san viet trong slippers", "tran viet trong slippery", "tran viet trong 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 viet trong 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 viet trong slippers") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( tran viet trong slippers ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("tran viet trong slippers") or ("dung java java snippets"))) or ("locating bug code snippets"))*.