Perhaps you should try some spelling variations:
thanh thai » thanh hai, thanh tai, nhanh thai
tham duc » tham du, than duc, thach duc
nang cai » nang cao, nang tai, nang can
thai cua » than cua, tai cuc, tri cua
nang cap » nang cao, nang cham, nang phap
va thanh » gia thanh, ban thanh, va tinh
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
sac ky » cac ky, sai ky
su sac » su sach, su cac, su xac

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky ((nang cai) or (nang cap)) hoi. hieu va ((tham duc) OR (pham duc)) va thanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky ((nang cai) OR (nang cap)) hoi. hieu va ((tham duc) OR (pham duc)) va thanh thai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ky ((nang cai) or (nang cap)) hoi. hieu va ((tham duc) OR (pham duc)) va thanh thai cua tre".
• Adding a wildcard symbol may retrieve word variants: su sac ky ((nang cai) or (nang cap)) hoi. hieu va ((tham duc) OR (pham duc)) va thanh thai cua tre*.