Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh lap » thanh san, phan lap, thanh hai
nang dai » nang dau, nang tai, lang dai
hieu van » hieu va, thien van, lieu va
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
chat xuc » chat huu, cam xuc, chao xu
ve triet » va trien, su triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
dai hai » dai han, dai hoi, dai tai
lap ve » dap ve, lap va, tap ve

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 dai hai. hieu van ((cac nuoc) or (chat xuc)) ban thanh lap ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang dai hai. hieu van ((cac nuoc) OR (chat xuc)) ban thanh lap ve triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang dai hai. hieu van ((cac nuoc) or (chat xuc)) ban thanh lap ve triet*.