sniff around
https://gyazo.com/35d1694da4b63871fa76ba99c489ab1e
source: [GJ部の皇紫音たちが探偵の真似をしているGIF画像|無料GIF画像検索 GIFMAGAZINE 489587] sniff (a)round: ⦅くだけて⦆ (情報・秘密などを求めて)かぎまわる.
⦅主に英・くだけて⦆ 〈人・組織などが〉〈恋人・客・従業員など〉を手に入れる.
e.g. His engagement hasn't stopped him from sniffing around other girls.
e.g. Rival companies have been sniffing around her for years.