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