bohren
to drill
To make a hole in a solid material with a tool, usually a drill.
Er bohrt ein Loch in die Wand, um das Bild aufzuhängen.
He is drilling a hole in the wall to hang up the picture.

to drill / probe
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to drill
To make a hole in a solid material with a tool, usually a drill.
Er bohrt ein Loch in die Wand, um das Bild aufzuhängen.
He is drilling a hole in the wall to hang up the picture.

The meaning of 'bohren' (to drill / probe) is very context-dependent. If it is about tools, it means making a hole. In connection with questions, it means 'to keep asking persistently'. The reflexive form 'sich bohren' (to bore its way) describes slow penetration.
Der Dorn bohrte sich langsam in seinen Finger.
The thorn slowly bored into his finger.
In the literal meaning, the construction 'ein Loch in etwas (Akkusativ) bohren' (to drill a hole into something) is often used. The preposition 'in' indicates where the hole is made.
Ich muss ein Loch in die Decke bohren, um die Lampe aufzuhängen.
I have to drill a hole in the ceiling to hang up the lamp.
In the figurative meaning of asking questions, 'bohren' (to probe) is often combined with the preposition 'nach'. You probe 'nach Informationen' (for information) or 'nach der Wahrheit' (for the truth).
Der Anwalt bohrte weiter, bis der Zeuge die Wahrheit sagte.
The lawyer kept probing until the witness told the truth.
The construction 'sich in etwas bohren' (to bore into something) is reflexive and always uses the preposition 'in' with the accusative. It describes a penetrating, often slow movement.
Der Splitter hat sich tief ins Holz gebohrt.
The splinter has bored deep into the wood.
The expression 'in der Nase bohren' (to pick one's nose) is a fixed phrase. It is used colloquially and is considered rude behavior.
Das Kind hat während des ganzen Films in der Nase gebohrt.
The child picked his nose throughout the entire film.
to sting / stab
'stechen' and 'bohren' both have to do with something going into a material or into the skin. 'stechen' is used more for something pointed and often for a small, quick injury, for example with a needle or from an insect. 'bohren' fits when you make a hole in a solid material with a tool, for example in wood or in a wall. The words can be confused because in both cases something penetrates. In practice: a needle or an insect 'sticht', while a drill 'bohrt'.

Am Samstag bohrt Paul ein Loch in die Wand für das neue Regal.
On Saturday, Paul drills a hole in the wall for the new shelf.
Die Ärztin sticht mir kurz in den Finger, um Blut zu nehmen.
The doctor briefly pricks my finger to take blood.