Perhaps you should try some spelling variations:
"tran vang cua snippets" » "tran van cua snippets", "tran dang cua snippets", "tran quang cua snippets", "tran mang cua snippets", "tran hang cua snippets", "tran tang cua 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: (((("tran vang cua snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("tran vang cua snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( tran vang cua snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("tran vang cua snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.