• 扱あつかう — to handle; to deal with; to manage
• 取とり扱あつかう — to handle; to deal in
• 取扱とりあつかい — handling; treatment
• 扱あつかい — treatment; handling
• 取扱説明書とりあつかいせつめいしょ — instruction manual
• 取扱店とりあつかいてん — authorized dealer; retailer

扱 is phono-semantic: the radical 扌 marks “hand; action,” while 及 provides the sound and the idea of “reach/extend a hand.” Together they point to taking something in hand and managing it. Nuance: 扱う is general “handle/deal with,” while 操作 (operate) or 操る (to control, often skillfully) imply more technical control.