Perhaps you should try some spelling variations:
"danh thuc cac snippets" » "dan thuc cac snippets", "anh thuc cac snippets", "dinh thuc cac snippets", "danh thuc cach snippets", "danh tuc cac snippets", "danh phuc 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: (((("danh thuc 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: (((("danh thuc cac snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( danh thuc cac snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("danh thuc cac snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.