Subject + caution; advise +object + recognize; acknowledge

I am in limbo about the syntax of a certain sentence I am formulating. To me, the following sentence (with the alternative word choice combinations) is intelligible and grammatical; however, when I did a corpus search, to my surprise, only a handful of search results came out, which made me a bit doubtful. Can you guys tell me how it reads to you?

They cautioned (advised) researchers to acknowledge (recognize) that…

At first, I thought the reason for the low search result was because the verb caution is usually followed by a negative action (not to). But then, why there also came low search results for the verb advise?

Thank you!