There was something mysterious about the old recluse, that demanded deep investigation.

A deeper investigation might have unearthed things nobody wanted brought to the surface.

But in the present case, he finds himself involved in deep investigation and analysis.

"What we have to do is have a greater exchange of information and deeper investigation, without touching the legitimate companies."

It needs deeper investigation, but we can say that we are at the beginning of something really interesting.

The impact of such interaction is still waiting deeper investigations.

A deeper investigation by the new board found addiitonal problems.

These stories must be dissected, and once a deep investigation is done, they carry a meaning which drives the plot of the novel.

The city's new Cardinal has pressed insistently for a deeper investigation.

Geffrard ordered a deep investigation and a public execution was held.