Looking on the internet deeply has found these results:

I am not sure what does this mean. is the most popular phrase on the web.

I am not sure what this means. 1659,000 results on the web	I am not sure what does this mean. 11,860,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
I'm ignoring it, but we don't know for sure what this means. I am not sure what proportionality means. Mr Evans, I am glad you are here because I am not quite sure what this question means. I'm ignoring it, but we don't know for sure what this means. I'm not sure what you mean. I can assure this House I am not a lobbyist for anybody, and, as to merchants of death, we do not meet many of them in Bolton market, so I am not sure what she means. I am not sure what that means. I'm not sure what this means.	I can assure this House I am not a lobbyist for anybody, and, as to merchants of death, we do not meet many of them in Bolton market, so I am not sure what she means. I'm not sure what this means. I'm not sure what you mean. Sorry, I'm not sure what you mean. I'm not sure what that means. I'm not sure what you mean. I am not sure what proportionality means. I am not sure what that means.

I am not sure what this means.

1659,000 results on the web

I am not sure what does this mean.

11,860,000 results on the web

More popular!

I'm ignoring it, but we don't know for sure what this means.
I am not sure what proportionality means.
Mr Evans, I am glad you are here because I am not quite sure what this question means.
I'm ignoring it, but we don't know for sure what this means.
I'm not sure what you mean.
I can assure this House I am not a lobbyist for anybody, and, as to merchants of death, we do not meet many of them in Bolton market, so I am not sure what she means.
I am not sure what that means.
I'm not sure what this means.

I can assure this House I am not a lobbyist for anybody, and, as to merchants of death, we do not meet many of them in Bolton market, so I am not sure what she means.
I'm not sure what this means.
I'm not sure what you mean.
Sorry, I'm not sure what you mean.
I'm not sure what that means.
I'm not sure what you mean.
I am not sure what proportionality means.
I am not sure what that means.