Perhaps you should try some spelling variations:
tham thuc » nham thuc, tam thuc, thai thuc
pham thuc » phap thuc, pham chuc, nham thuc
nang cai » nang cao, nang tai, nang cap
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
cai hoa » cau hoa, cam hoa, dai hoa
hieu va » lieu va, hieu qua
va lanh » va lang, va danh, va hanh
dao cua » dai cua, day cua, dan cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang cai hoa. hieu va ((tham thuc) or (pham thuc)) va lanh dao cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang cai hoa. hieu va ((tham thuc) OR (pham thuc)) va lanh dao cua te.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang cai hoa. hieu va ((tham thuc) or (pham thuc)) va lanh dao cua te*.