Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
xanh tai » hanh tai, anh tai, vanh tai
hieu van » hieu va, thien van, lieu va
van chat » cao chat
chat cuu » chat huu, chat cua, cham cuu
cuu tre » cau tren, cau treo
xanh di » danh di, vanh dai
sach ky » sac ky, sach y, sach ty
cao hoi » cau hoi, co hoi, cao hoc
cua tre » cua te, cua triet, dua tren
cuu va » cuu van, cuu ve

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 ky nang cao hoi. hieu van chat cuu va ((xanh di) or (xanh tai)) ((cuu tre) OR (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky nang cao hoi. hieu van chat cuu va ((xanh di) OR (xanh tai)) ((cuu tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ky nang cao hoi. hieu van chat cuu va ((xanh di) or (xanh tai)) ((cuu tre) OR (cua tre))".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky nang cao hoi. hieu van chat cuu va ((xanh di) or (xanh tai)) ((cuu tre) OR (cua tre))*.