Perhaps you should try some spelling variations:
thanh doi » thanh loi, thanh moi, thanh do
van chat » cao chat
hieu van » hieu va, thien van, lieu va
doi cua » dai cua, hoi cua, dong cua
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, duc va
y nang » ky nang, ly nang, v nang

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

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