Getting distracted with

The expression 気(き)が散(ち)る means “to be distracted” or “to lose focus”. Your 気 (spirit) does the action of 散る (to scatter).

It says that something scatters your attention and makes concentration difficult. The distraction is usually unwanted.

The phrase can express mild frustration at being unable to concentrate.

Dictionary Definition

一(ひと)つの事(こと)に気持(きも)ちが集中(しゅうちゅう)できない。

Cannot concentration on even one thing.

Goo Dictionary

Examples

Distracted by test scores with 気が散る

Manga panel from 美少女戦士セーラームーン showing example of Distracted by test scores with 気が散る.
美少女戦士セーラームーン » Volume 8 » Page 305

Ami is used to getting the top grade on mock exams, but when another name starts tying her scores, she begins to get flustered. Her friend Minako suggests they investigate the person behind the name, but Rei isn’t so sure.

美奈子(みなこ):
「あのままじゃ 亜美(あみ)ちゃん気(き)が散(ち)って成績(せいせき)が落(お)ちちゃうわ!」
“The way things are, Ami-chan'll be distracted, and her grades will drop!”
レイ:
「こんなコト 始(はじ)めたってのがバレた時(とき)の方(ほう)が亜美(あみ)ちゃんの気(き)が散(ち)ると思(おも)うけど」
“I think Ami-chan will be more distracted when she finds out we've started something like this.”

Don't take your focus off the lynx with 気が散る

Manga panel from 骨ドラゴンのマナ娘 showing example of Don't take your focus off the lynx with 気が散る.
骨ドラゴンのマナ娘 » Volume 1 » Page 85

In order to make money to survive and continue her path of becoming a mage, Eve takes on a request to defeat a fanged lynx that has been attacking a merchant in the forest. She attempts to use her new magick staff against the beast, but no magick materializes from it.

イブ:
「魔女(まじょ)なのに 魔法(まほう)出(で)ない」
“Even though I'm a mage, magick won't come out.”
ネム:
「こら 気(き)を散(ち)らすな」
“Hey now, don't lose focus!”