Perhaps you should try some spelling variations:
tham thuc » pham thuc, tam thuc, thai thuc
phap thuc » phap thu, phap hoc, phap tu
nham thuc » nhan thuc, nam thuc, nham thu
lang mai » lang dai, lang hai, lang man
hieu van » hieu va, thien van, lieu va
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo
mai hoi » mai khoi, dai hoi, lai hoi
ky lang » ky nang, ky dang, ky tang
sac ky » cac ky, sai ky
vi cuu » vi luu, vinh cuu
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky lang mai hoi. hieu van ((tham thuc) or (((phap thuc) or (nham thuc)))) va hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky lang mai hoi. hieu van ((tham thuc) OR (((phap thuc) OR (nham thuc)))) va hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu sac ky lang mai hoi. hieu van ((tham thuc) or (((phap thuc) or (nham thuc)))) va hanh vi cuu tre*.