Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van viet da snippets" » "san viet da snippets", "gian viet da snippets", "tran viet da snippets", "van viet dao snippets", "van viet dat snippets", "van viet ha 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: (((("van viet da snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("van viet da snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van viet da snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van viet da snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.