Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
thu sach » tu sach, thuoc sach, thu hoach
hang di » hang doi, hang vi, hang dien
hanh di » hanh vi, hanh de, danh di
cao luc » bao luc, cao duc, cao suc
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
va cao » va cac, va co, va dao
luc va » duc va, tuc va, loc va
y nang » ky nang, ly nang, v nang
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: ((thu sach) OR (thuat sach)) y nang x hoi. hieu va cao luc va ((hanh di) or (hang di)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuat sach)) y nang x hoi. hieu va cao luc va ((hanh di) OR (hang di)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) OR (thuat sach)) y nang x hoi. hieu va cao luc va ((hanh di) or (hang di)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) OR (thuat sach)) y nang x hoi. hieu va cao luc va ((hanh di) or (hang di)) cua tre*.