Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
hanh dao » lanh dao, thanh dat, thanh dam
dao cua » dai cua, day cua, dan cua
va hanh » van hanh, va thanh, va danh
cam tuc » cam tu, nam thuc, dam thuc
xang xa » lang xa, mang xa, ang xa
su sach » so sach, vu sach
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: ((thu sach) or (su sach)) ty xang xa hoi. hieu van ((cam tuc) or (cam xuc)) va hanh dao cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (su sach)) ty xang xa hoi. hieu van ((cam tuc) OR (cam xuc)) va hanh dao cua tre.
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (su sach)) ty xang xa hoi. hieu van ((cam tuc) or (cam xuc)) va hanh dao cua tre*.