Perhaps you should try some spelling variations:
day danh » day manh, dai danh, dao danh
vinh cuu » dinh cuu, sinh cua, dinh cu
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
thi van » thi lan, thi hanh, thi nang
thu day » thuc day, thu da, thu dac
vi luu » vi lua

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky nang x ho. ((hieu ve) or (thi van)) nam thu day danh ((vinh cuu) or (vi luu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang x ho. ((hieu ve) OR (thi van)) nam thu day danh ((vinh cuu) OR (vi luu)) tre.
• Adding a wildcard symbol may retrieve word variants: so sach ky nang x ho. ((hieu ve) or (thi van)) nam thu day danh ((vinh cuu) or (vi luu)) tre*.