Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
cau tren » cu tren, dau tren, ca tren
hieu van » hieu va, thien van, lieu va
cuc ban » cua ban, cuu ban, duc ban
tai cau » tai cac, tai cao
han tai » hang tai, nhan tai, van tai
cac ban » cac dan, cac van, can ban
su sach » so sach, vu sach
van cam » van nam, van lam, van cau
nang xa » nang x, lang xa, nang ma

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (thuat sach)) ky nang xa hoi. hieu van cam ((cuc ban) OR (cac ban)) han tai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (thuat sach)) ky nang xa hoi. hieu van cam ((cuc ban) OR (cac ban)) han tai cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (thuat sach)) ky nang xa hoi. hieu van cam ((cuc ban) OR (cac ban)) han tai cau tren".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (thuat sach)) ky nang xa hoi. hieu van cam ((cuc ban) OR (cac ban)) han tai cau tren*.