Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
nang xa » nang x, lang xa, nang ma
van cam » van lam, van cau, van dam
luu tre » luu tru, cuu tre, luy tre
y nang » ky nang, ly nang, v nang
dan vi » doan vi, don vi, dan va
vi luu » vi lua
tu ca » tu cua, tu can, tu cay

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y nang xa hoi. thien ((van cam) or (van nam)) ((tu ca) or (tu cac)) dan vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang xa hoi. thien ((van cam) OR (van nam)) ((tu ca) OR (tu cac)) dan vi luu tre.
• Adding a wildcard symbol may retrieve word variants: toc sach y nang xa hoi. thien ((van cam) or (van nam)) ((tu ca) or (tu cac)) dan vi luu tre*.