Perhaps you should try some spelling variations:
"nang thon cac snippets" » "nong thon cac snippets", "nang chon cac snippets", "nang thuong cac snippets", "nang thong cac snippets", "nang tho cac snippets"
"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: (((("nang thon cac snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("nang thon cac snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( nang thon cac snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("nang thon cac snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.