Why - according to Rashi - did Lavan search Rachel's tent twice?
Rashi #1: Because he knew his daughter to be particularly fidgety, and that, as such, she was the most likely person to have taken the Terafim.
Rashi #2 (in Divrei Hayamim 1, 29:21: The Torah writes "Vayavo be'Ohel Rachel" to clarify "be'Ohel Yakov" that preceded it. 1
See Rashi there as to why the Torah separates them.
What is "Neged Achai v'Achecha"? How can they know whether something was stolen from Lavan?
Tosfos ha'Shalem (3): It is in front of your 'brothers' (who accompanied you), from sons of Yishmael and Keturah, who are related to me.
Ohr ha'Chayim: Ownership is proven through giving Simanim. 1 It must be in front of my brothers and yours; he did not trust Lavan's brothers alone, for they are like him.
Ha'Emek Davar: It was recognized the difference between Kelim of Yisrael and of Nochrim.
How will Simanim prove anything? If Yakov or his family stole something, they could see the Siman when they took it. Kelim that Yakov bought or made, Lavan could see the Siman when he searched for his Terafim! Lavan claimed that Yakov took things just before he fled. There are Simanim that a thief would not see at the time he steals, e.g. the exact length and width of a garment, nor would Lavan know them from his search. Alternatively, Lavan's 'brothers' were regular in his house. Did you find one Kli for which one of your brothers can give a Siman?! However, Ohr ha'Chayim's final words imply unlike this. (PF)
Why did Yakov mention "Klei Beisecha"? Lavan accused him only of stealing his gods!
Refer to 31:36:1:1.
Malbim (32) You think that I stole your gods, lest they tell you what I stole from you. Did you find anything of yours?!