Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van viet oi snippets" » "san viet oi snippets", "gian viet oi snippets", "tran viet oi snippets", "van viet doi snippets", "van viet voi snippets", "van viet o 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 oi 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 oi snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van viet oi snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van viet oi snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.