Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
nang mai » nang tai, lang mai, nang cai
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
cam luc » cau luc
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty ((nang mai) OR (nang ma)) hoi. hieu ve ((cam luc) or (cam xuc)) van hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((nang mai) OR (nang ma)) hoi. hieu ve ((cam luc) OR (cam xuc)) van hanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((nang mai) OR (nang ma)) hoi. hieu ve ((cam luc) or (cam xuc)) van hanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ty ((nang mai) OR (nang ma)) hoi. hieu ve ((cam luc) or (cam xuc)) van hanh dai cua tre*.