Explanation #1: Rashi explains that the Gemara is referring to examining underneath the bed.

Question: In that case, it ought not to have mentioned 'ha'Cholekes', only Mafsekes', and no more?

Explanation #2: We are therefore forced to say that the bed divides the room. 'Mafsekes' then means that it is placed in the middle of the room and 'Cholekes' that it goes from wall to wall, and that one cannot therefore get past without either climbing over the bed or crawling underneath it.

Explanation #2 (cont.): And the Gemara is not saying that te far side of the bed does not require Bedikah.

Support: And this is also implied by the Yerushalmi and by the Tosefta, which, citing Raban Shimon ben Gamliel, states that in a case where 'a bed that divides a room into two, and under which are lying wood and stones, it is only outside it that requires Bedikah, but not inside it'.

Clarification: The Yerushalmi implies that the Beraisa that inserts wood and stones has the text 'Ein Tzarich Bedikah'.

Implied Question: And the reason that the Gemara does not answer here that that Beraisa is speaking where there are wood and stones underneath it ...

Answer: Is because it does not believe that this is a reason to be Patur from Bedikah, only because it is not the way to bend down and pass underneath the bed (whether there are stones there or not).

Explanation #1: The Gemara establishes one of the Beraisos where the bed is high - and that is where it is Chayav Bedikah, because, since the legs are tall, it is possible to pass underneath it to the other side without bowing low.

Explanation #2: Alternatively, when the bed is high, it does not require Bedikah, since it is difficult to clamber across the top.

Alternative Text: There are some texts which learn 'Ein Tzarich' in the first Beraisa, and 'Tzarich' in the second one ...

Ramifications: in which case the Tana mentions 'wood and stones arranged underneath it' (in the second Beraisa) for the Chidush (that although there is wood underneath it, Bedikah is nevertheless required).

Third Text: Whereas according to Rabeinu Chananel, both Beraisos have the text 'Ein Tzarich Bedikah' ...

Clarification: And the Gemara's Kashya is why the first Beraisa does not require wood and stones underneath it (in order to exempt the owner from Bedikah), whereas the second one does.

Clarification: This explains why one is only Patur because of the danger involved.

Implied Question: In the case of Mapo'les (a wall that collapsed), why does the Gemara imply that if a dog is able to search for the Chametz, it is not considered destroyed and one is Chayav to search for it (in spite of the danger)?

Answer: The Ri explains that the case there is different, inasmuch as it is speaking about Chametz that is known to be there, so the Chachamim troubled the owner to hire workers to dig with a spade and a pick-ax, if need be; whereas our Sugya is speaking about Safek Chametz, which the Chachamim did not bother him to search for.

Implied Question: How will we reconcile this Sugya with the Mishnah in Pirkei Avos (1:3), which stated 'Do not be like servants who serve the master in order to receive reward ... '?

Answer: That speaks where one has specifically in mind that if the good that one expects does not materialize, one is sorry about that the Tzedakah that he gave.

Answer (cont.): Whereas someone who is not sorry, is a complete Tzadik.

Proof: And this is also implied at the beginning of Maseches Rosh ha'Shanah (4.) and in the first Perek of Bava Basra (10:).

Clarification: The Gemara learns this from the word "es (Artz'cha)", implying that what is secondary to your land.

Question: Now (that that we learn Halichah from Chazarah) why do we need the word "es"?

Answer: Since the Torah needs to write this Pasuk on account of the Chidush of "Artz'cha", it adds the word "es" to teach us the previous Chidush, even though it is not needed.

Clarification (Part 1): The Ri explains that Rav prefers to extrapolate from 'Chitzonos', because the Mishnah mentions it first

Clarification (Part 2): Whilst Shmuel prefers to extrapolate from 'Elyonos', since Elyonos; refers to 'Chitzonos', and comes to qualify them.