Perhaps you should try some spelling variations:
"dung vien cac snippets" » "duong vien cac snippets", "dung viet cac snippets", "dung tien cac snippets", "dung vien bach snippets", "dung vien dai snippets", "dung vien da snippets"
"anh java java snippets" » "anh 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: (((("anh java java snippets") or ("dung vien cac snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("anh java java snippets") OR ("dung vien cac snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( anh java java snippets ) or ( dung vien cac snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("anh java java snippets") or ("dung vien cac snippets"))) or ("locating bug code snippets"))*.