Perhaps you should try some spelling variations:
"using ibm code snippets" » "using rbf code snippets", "using lbm code snippets", "using ibm code slippers"
"duong duc dan snippets" » "luong duc dan snippets", "duong qua dan snippets", "dang duc dan snippets", "duong duoc dan snippets", "duong duc tan snippets", "duong duc dai snippets", "duong duc dan slippers"
"locating bug code snippets" » "locating bug code slippers", "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 ibm code snippets") or ("duong duc dan snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using ibm code snippets") OR ("duong duc dan snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using ibm code snippets ) or ( duong duc dan snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using ibm code snippets") or ("duong duc dan snippets"))) or ("locating bug code snippets"))*.