Perhaps you should try some spelling variations:
"dung sach hoan snippets" » "dung sach han snippets", "dung cach hoan snippets", "dung hach toan snippets", "duong sach hoan snippets", "dung sai hoan snippets", "dung cac hoan snippets"
"using a code snippets" » "using a core snippets"
"locating bug code snippets" » "locating bug core snippets", "locating bung code snippets", "locating bugs code 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: (((("using a code snippets") or ("dung sach hoan snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using a code snippets") OR ("dung sach hoan snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using a code snippets ) or ( dung sach hoan snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using a code snippets") or ("dung sach hoan snippets"))) or ("locating bug code snippets"))*.