Perhaps you should try some spelling variations:
cham truc » cau truc, nham thuc, pham thuc
ban thanh » ban hanh, ban hang
van cham » van chat, van tham, va cham
thu sach » thuat sach, thuoc sach, thu hoach
va thanh » gia thanh, va tinh, le thanh
hieu van » hieu va, thien van, lieu va
tu sach » su sach, te sach, tu cach
su viet » so viet
v nang » va nang, vu nang, van nang
do su » do sut, do tu, co su

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) or (thu sach)) v nang x ho. hieu van cham truc ((va thanh) or (ban thanh)) do su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) v nang x ho. hieu van cham truc ((va thanh) OR (ban thanh)) do su viet.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) v nang x ho. hieu van cham truc ((va thanh) or (ban thanh)) do su viet*.