Perhaps you should try some spelling variations:
"tran truan doi snippets" » "tran tuan doi snippets", "tan tran doi snippets", "tran xuan doi snippets", "tran truyen doi snippets", "tran quan doi snippets", "tran khuan doi 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: (((("dung java java snippets") or ("tran truan doi snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung java java snippets") OR ("tran truan doi snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung java java snippets ) or ( tran truan doi snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung java java snippets") or ("tran truan doi snippets"))) or ("locating bug code snippets"))*.