What is the meaning of 'dabei' in this sentence?
What is the meaning of dabei in "Sie taumelt sich weiter und stützt sich dabei mit der Hand gegen die Mauer,"? Can you give more sentence examples like that using dabei?
The verb entzweischneiden means 'to cut into two'. If so, is there 'entdreischneiden'?
What is the meaning of na so was?
'dabei' means something like 'during' here, doing something at the same time (German: 'während, währenddessen').
No, 'entdreischneiden' does not exist in German. To be honest: I think, this word is obsolescent in modern German, at least I didn´t heared or used it for a long time (decades).
With this expression we express, that we are surprised by a situation or something or we do not understand something completely. I don´t now a similar expression in English, but Pons counts i. e. "bejesus!", "my my", "Jesus Murphy", "well, well" and some more as a translation.
Entzwei schneiden is definitely oldfashioned and poetic, in daily usage you will rather use "auseinander schneiden".