Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
ban thanh » ban hanh, ban hang
cau tren » cu tren, dau tren, ca tren
thanh ha » thanh hoa, thanh hai, nhanh ha
hieu van » hieu va, thien van, lieu va
van cac » van hac, van cau, van bac
tu cach » tu cac
ky tang » ky nang, ky dang, kho tang
ky lang » ky nang, ky dang, tay lang
du ban » dua ban, duc ban, du bao
ha cau » ha chau, hoa cau, pha cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cach) or (thuoc sach)) ((ky lang) or (ky tang)) xa hoi. hieu van cac du ban thanh ha cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thuoc sach)) ((ky lang) OR (ky tang)) xa hoi. hieu van cac du ban thanh ha cau tren.
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (thuoc sach)) ((ky lang) or (ky tang)) xa hoi. hieu van cac du ban thanh ha cau tren*.