Perhaps you should try some spelling variations:
thien van » thi van
toc sach » hoc sach, doc sach, thuoc sach
cau tren » cu tren, dau tren, ca tren
nang xa » nang x, lang xa, nang ma
cuu tre » cua tre, cau treo
cam tu » cam thu, nam tu, tam tu
y nang » ky nang, ly nang, v nang
ca dan » cac dan, ca dao
dan vi » doan vi, don vi, dan va
dam tu » nam tu, tam tu, dam thuc

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 y nang xa hoi. thien van ((cam tu) OR (dam tu)) ca dan vi ((cuu tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang xa hoi. thien van ((cam tu) OR (dam tu)) ca dan vi ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y nang xa hoi. thien van ((cam tu) OR (dam tu)) ca dan vi ((cuu tre) or (cau tren))".
• Adding a wildcard symbol may retrieve word variants: toc sach y nang xa hoi. thien van ((cam tu) OR (dam tu)) ca dan vi ((cuu tre) or (cau tren))*.