Perhaps you should try some spelling variations:
"duong dan cach snippets" » "duong dang cach snippets", "huong dan cach snippets", "duong van cach snippets", "duong dan cac snippets", "duong dan canh snippets", "duong nhan cach snippets"
"anh java java snippets" » "anh 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: (((("anh java java snippets") or ("duong dan cach snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("anh java java snippets") OR ("duong dan cach snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( anh java java snippets ) or ( duong dan cach snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("anh java java snippets") or ("duong dan cach snippets"))) or ("locating bug code snippets"))*.