“在手边”的英语可以翻译为：at hand ...

你应该保管好这份手册，这样随时想用都能马上在手边找到。You may want to keep this brochure safe, so you have it to hand whenever you may need it.我的书好像不在手边.I don't seem to have my book to hand.要经常把参考书摆在手边.Always have your reference books near at...