Perhaps you should try some spelling variations:
"long vien cac snippets" » "long bien cac snippets", "dong vien cac snippets", "long viet cac snippets", "long vien bach snippets", "long vien dai snippets", "long vien da 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: (((("long vien 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: (((("long vien cac snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( long vien cac snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("long vien cac snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.