Perhaps you should try some spelling variations:
"hoc thanh cua snippets" » "hoc nhanh cua snippets", "hoan thanh cua snippets", "hoc phan cua snippets", "hoc tranh cua snippets", "hoc than cua snippets", "hoc hanh cua snippets"
"dung java java snippets" » "dung va java 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: (((("hoc thanh cua snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("hoc thanh cua snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( hoc thanh cua snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("hoc thanh cua snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.