Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cao luc » bao luc, cao duc, cau luc
cao suc » cao su, cao duc
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
v nang » va nang, vu nang, van nang
sach v » sach va, sach y, sach 2
dan di » danh di, dan da, dan li
dan de » dan den, dang de, van de

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

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