Perhaps you should try some spelling variations:
thanh phan » thanh pho, thanh san, thanh toan
thanh van » thanh san, thanh toan, thanh nhan
hieu van » hieu va, thien van, lieu va
qua ban » cua ban, qua quan
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
dai hoa » dai khoa, dai hoc, dai hoi
mai hoa » mai khoa, ma hoa, lai hoa
ky dang » ky nang, ky danh
cua tre » cua te, cuu tre, cua triet
van ca » van cau, van cua, dan ca
ca qua » cau qua, cac qua, ca quan

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 dang ((mai hoa) or (dai hoa)). hieu van ca qua ban ((thanh van) or (thanh phan)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky dang ((mai hoa) OR (dai hoa)). hieu van ca qua ban ((thanh van) OR (thanh phan)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky dang ((mai hoa) or (dai hoa)). hieu van ca qua ban ((thanh van) or (thanh phan)) cua tre*.