Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
bat thanh » ban thanh, bac thanh, dat thanh
thanh ve » hanh ve, thanh va, thanh vien
cao suc » cao su, cao duc
cao luc » bao luc, cao duc, cau luc
hieu va » lieu va, hieu qua
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, v nang, may nang
ve cua » le cua, de cua, te cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ((y nang) or (ly nang)) xa hoi. hieu va ((cao luc) OR (cao suc)) bat thanh ve cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ((y nang) OR (ly nang)) xa hoi. hieu va ((cao luc) OR (cao suc)) bat thanh ve cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ((y nang) or (ly nang)) xa hoi. hieu va ((cao luc) OR (cao suc)) bat thanh ve cua tre".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ((y nang) or (ly nang)) xa hoi. hieu va ((cao luc) OR (cao suc)) bat thanh ve cua tre*.