Perhaps you should try some spelling variations:
"dung van lang snippets" » "duong van lang snippets", "dung va lang snippets", "dang van lang snippets", "dung van nang snippets", "dung van hang snippets", "dung van lang slippers"
"using c code snippets" » "using lc code snippets", "using a code snippets", "using _ code snippets", "using cfd code snippets", "using c code slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code 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: (((("using c code snippets") or ("dung van lang snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using c code snippets") OR ("dung van lang snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using c code snippets ) or ( dung van lang snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using c code snippets") or ("dung van lang snippets"))) or ("locating bug code snippets"))*.