Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"viet duc hoc snippets" » "viet dung hoc snippets", "viet duoc hoc snippets", "viet luc hoc snippets", "viet du hoc 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: (((("viet duc hoc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("viet duc hoc snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( viet duc hoc snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("viet duc hoc snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.