Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
va chat » van chat, va phat, cao chat
hanh le » thanh le, hanh ve, hanh de
cua tre » cua te, cuu tre, cua triet
v nang » va nang, vu nang, van nang
y nang » ky nang, ly nang, may nang
uoc va » nuoc va, duoc va, quoc va
loc va » hoc va, luc va
le cua » ly cua
o hoi » co hoi, o hoc, o hai

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 ((y nang) OR (v nang)) o hoi. lieu va chat ((uoc va) or (loc va)) hanh le cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((y nang) OR (v nang)) o hoi. lieu va chat ((uoc va) OR (loc va)) hanh le cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((y nang) OR (v nang)) o hoi. lieu va chat ((uoc va) or (loc va)) hanh le cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((y nang) OR (v nang)) o hoi. lieu va chat ((uoc va) or (loc va)) hanh le cua tre*.