Perhaps you should try some spelling variations:
bo sach » co sach, hoc sach
sach lo » sach dao, sach doi, sach hoi
cua tre » cua te, cuu tre, cua triet
va hanh » van hanh, va thanh, va danh
van hai » van ha, van chat, van hanh
van hac » van hoc, van ha, van chat
lo nang » ho nang, ly nang, loai nang
ca tren » cau tren, cu tren, la tren
tuc va » thuc va, truc va, tuc xa
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: bo sach lo nang x hoi. thien ((van hac) or (van hai)) tuc va hanh vi ((cua tre) or (ca tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: bo sach lo nang x hoi. thien ((van hac) OR (van hai)) tuc va hanh vi ((cua tre) OR (ca tren)).
• Adding a wildcard symbol may retrieve word variants: bo sach lo nang x hoi. thien ((van hac) or (van hai)) tuc va hanh vi ((cua tre) or (ca tren))*.