Perhaps you should try some spelling variations:
"duong anh tong snippets" » "duong manh tong snippets", "duong xanh tong snippets", "duong vanh tong snippets", "duong anh trong snippets", "duong anh thong snippets", "duong anh dong 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: (((("duong anh tong snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("duong anh tong snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( duong anh tong snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("duong anh tong snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.