Perhaps you should try some spelling variations:
sach tru » sach truc, sach thu, sach tu
tru nang » tra nang, tri nang, truc nano
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
van hanh » van thanh, ban hanh, van anh
hanh dai » hanh tai, hanh dao, vanh dai
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
cam tuc » cam xuc, cam tu, dam thuc
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: tu sach tru nang xa hoi. hieu van ((cam tuc) or (nam thuc)) van hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tru nang xa hoi. hieu van ((cam tuc) OR (nam thuc)) van hanh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach tru nang xa hoi. hieu van ((cam tuc) or (nam thuc)) van hanh dai cua tre*.