Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"den viet voi snippets" » "dien viet voi snippets", "dan viet voi snippets", "de viet voi snippets", "den viec voi snippets", "den viet doi snippets", "den viet duoi 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: (((("den viet voi snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("den viet voi snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( den viet voi snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("den viet voi snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.