Perhaps you should try some spelling variations:
nang thai » nang tai, dang thai, lang thai
thai cua » than cua, tai cuc, tri cua
cam thue » cam thu, lam thue, nam thue
hieu va » lieu va, hieu qua
da nang » cam nang, kha nang, cao nang
thue da » thue dat, thue va, thu da
tu sach » thu sach, su sach, te sach
ly nang » ky nang, ly hang, ly vang
y nang » ky nang, v nang, may nang
va cam » va cham, va cac, va cao
cua te » cua tu
5 hoi » o hoi

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 ((y nang) or (ly nang)) ((5 hoi) or (xa hoi)). hieu va cam thue da nang thai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((y nang) OR (ly nang)) ((5 hoi) OR (xa hoi)). hieu va cam thue da nang thai cua te.
• Adding a wildcard symbol may retrieve word variants: tu sach ((y nang) or (ly nang)) ((5 hoi) or (xa hoi)). hieu va cam thue da nang thai cua te*.