Perhaps you should try some spelling variations:
"lang chon cac snippets" » "nang chon cac snippets", "lang phong cac snippets", "liang chen cac snippets", "lang cho cac snippets", "lang thong cac snippets", "lang hoc 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: (((("lang chon 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: (((("lang chon cac snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( lang chon cac snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("lang chon cac snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.