Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, anh thai
thien van » thi van
hanh tai » thanh tai, hang tai, han tai
co sach » bo sach, cuon sach, hoc sach
xuc van » duc van, luc van, vuc van
hac xuc » chat xuc
van hac » van hoc, van ha, van hai
ky tang » ky nang, ky dang, kho tang
ky lang » ky nang, ky dang, tay lang
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: co sach ((ky lang) OR (ky tang)) xa hoi. thien van hac xuc van ((hanh thai) or (hanh tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ((ky lang) OR (ky tang)) xa hoi. thien van hac xuc van ((hanh thai) OR (hanh tai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach ((ky lang) OR (ky tang)) xa hoi. thien van hac xuc van ((hanh thai) or (hanh tai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: co sach ((ky lang) OR (ky tang)) xa hoi. thien van hac xuc van ((hanh thai) or (hanh tai)) cua tre*.