Perhaps you should try some spelling variations:
nang thai » nang tai, dang thai, lang thai
thai cua » than cua, tai cuc, tri cua
tu sach » thu sach, su sach, te sach
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
thue va » thuc va, thuyet va, thuat va
cua tre » cua te, cuu tre, cua triet
y lang » o lang, _ lang, tay lang
va cam » va cham, va cac, va cao

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