Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
dat quoc » dat nuoc, dat duoc, dan quoc
dan thai » dang thai, dan than, ban thai
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
van dat » van dao, van dau, dan dat
quoc va » nuoc va, duoc va, quoc gia
dan thi » dang thi, tran thi, dinh thi
cuu tre » cua tre, cau tren, cau treo

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 ky lang xa hoi. hieu van dat quoc va ((dan thai) or (dan thi)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky lang xa hoi. hieu van dat quoc va ((dan thai) OR (dan thi)) cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky lang xa hoi. hieu van dat quoc va ((dan thai) or (dan thi)) cuu tre*.