Perhaps you should try some spelling variations:
"python using java snippets" » "python using data snippets"
"van nang du snippets" » "van quang du snippets", "van ban du snippets", "van dong du snippets", "van nang tu snippets", "van nang luc snippets", "van nang doc 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 nang du 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 nang du snippets") OR ("python using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( van nang du snippets ) or ( python using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("van nang du snippets") or ("python using java snippets"))) or ("locating bug code snippets"))*.