Perhaps you should try some spelling variations:
thanh phan » thanh pho, thanh san, thanh toan
thanh hai » thanh hoa, thanh san
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van cam » van lam, van cau, van dam
duc ban » duc tan, duc van, dua ban
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: tu sach ky nang xa hoi. hieu ((van cam) or (van nam)) duc ban ((thanh hai) OR (thanh phan)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu ((van cam) OR (van nam)) duc ban ((thanh hai) OR (thanh phan)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. hieu ((van cam) or (van nam)) duc ban ((thanh hai) OR (thanh phan)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu ((van cam) or (van nam)) duc ban ((thanh hai) OR (thanh phan)) cua tre*.