Perhaps you should try some spelling variations:
dat tren » dat trong, dua tren
canh tay » canh tac, thanh tay, anh ta
cau tren » cu tren, dau tren, ca tren
van hanh » van thanh, ban hanh, van anh
cam luan » ham luan, pham luan, bai luan
sach ky » sac ky, sach y, sach ty
canh xa » canh va, canh tac, manh xay
tu sach » thu sach, su sach, te sach
va cam » va cham, va cac, va cao

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky ((canh xa) or (canh tay)) hoi. lieu va cam luan van hanh vi ((cau tren) or (dat tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((canh xa) OR (canh tay)) hoi. lieu va cam luan van hanh vi ((cau tren) OR (dat tren)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((canh xa) or (canh tay)) hoi. lieu va cam luan van hanh vi ((cau tren) or (dat tren))*.