Perhaps you should try some spelling variations:
"doc dan canh snippets" » "doc dan code snippets", "doc van canh snippets", "doc dan cach snippets", "doc dan hanh snippets", "duoc dan canh snippets", "hoc dan canh snippets", "doc dao canh snippets"
"locating bug core snippets" » "locating bug code snippets"
"python using java snippets" » "python using data 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: (((("python using java snippets") or ("doc dan canh snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("python using java snippets") OR ("doc dan canh snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( python using java snippets ) or ( doc dan canh snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("python using java snippets") or ("doc dan canh snippets"))) or ("locating bug core snippets"))*.